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Pages 1-20 of 52

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Pages 1-20 of 52

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Art. XLVII.—Notes on the Mineralogy of New Zealand. By S. Herbert Cox, F.C.S., F.G.S., Assistant Geologist & Inspector of Mines. [Read before the Wellington Philosophical Society, 21st October, 1882.] The following paper, which is in continuation of the one published in last year's volume* Trans. N.Z. Inst., vol. xiv., p. 418. of the “Transactions of the New Zealand Institute,” will be devoted to the non-metallic minerals. Non—Metallic Minerals.—Class I. Water. Water, H.—As a simple mineral this substance needs no comment, but, as pointed out by Dr. Hector (Handbook of New Zealand for Melbourne Exhibition, 1880, p. 102), New Zealand is singularly rich in springs of water that hold mineral salts in solution, and some of these are already noted for their valuable medicinal properties. Both hot and cold springs are found, the former being, with few exceptions, confined to the districts of the North Island where volcanic forces have been active during the latest tertiary period, and are not yet altogether dormant. A few thermal springs are found to escape from the upper mesozoic rocks in localities where the source of heat can only be attributed to chemical decomposition of bituminous matters and sulphides; and, in a few instances, warm waters spring from palæozoic rock-formations in the South Island. The cold mineral springs have a wider distribution, but have only, as yet, been examined from comparatively few localities. The mineral waters of New Zealand may be classified, from the analyses that have been made in the Colonial Laboratory, into the following groups:— Saline.—Containing chiefly chloride of sodium. Alkaline.—Containing carbonates and bicarbonates of soda and potash. Alkaline siliceous.—Waters containing much silicic acid, but changing rapidly on exposure to the atmosphere and becoming alkaline. Hepatic or sulphurous.—Waters, the prominent character of which is the presence of sulphuretted hydrogen and sulphurous acid. Acidic.—Waters in which there is an excess of mineral acids, such as hydrochloric and sulphuric acid.

From the analyses of the mineral waters by Mr. Skey, the principal results of which have been published,* Trans. N.Z. Inst., vol. x., p. 423. the following substances appear to be contained in solution:— Silicates of soda ” lime ” magnesia ” iron Silica Sulphate of soda ” potash ” alumina ” lime ” magnesia ” iron Chloride of sodium ” potassium ” calcium ” magnesium ” iron Phosphate of alumina Phosphoric acid Lithia Iron oxides Hydrochloric acid (free) Sulphuretted hydrogen Sulphuric acid (free) Bromide of magnesium Iodide ” Carbonic acid (free) Carbonates of soda ” potash ” magnesia ” lime Free ammonia Albuminoid ammonia. Non–Metallic Minerals.—Class II. Carbon and Boron. Graphite, C.—This mineral occurs somewhat widely distributed throughout New Zealand; but up to the present time has not been found in large enough quantities and of sufficient purity to induce anyone to work it

continuously. Prior to 1865, however, 7 tons of manufactured plumbago from Pakawau, Nelson, valued at £1,400, were exported, but the trade has not been continued. The first mention of its occurrence in New Zealand is by Dr. v. Hochstetter (New Zealand, 1863, p. 477, Eng. Ed.) where he says,—“The Bros. Curtis, in 1861, opened extensive beds of plumbago near Pakawau.“Dr. Hector also (Jurors' Rep. N. Z. Ex., 1865, pp. 34 and 417) mentions its occurrence at Pakawau, near Collingwood, as thick beds interstratified with metamorphosed shale. Compressed samples were found to be quite equal in colour and brilliancy to that commonly sold in paper packets for domestic purposes. Analyses of these samples showed that they contained:— (1.) (2.) (3.) Carbon 37.60 30.03 58.10 Water 2.00 1.35 2.68 Ash 60.40 68.62 39.22 100.00 100.00 100.00 He, also, in the same report (p. 267), mentions its occurrence as scales in the marble of the West Coast, and Mr. J. C. Crawford (Essay on the Geology of the Wellington Province, p. 5) says,—“Thin seams of an impure graphite are found at a great variety of places:—on the Pitone Road, near Wellington; at the Mungaroa Hill; at various points on the Rimutaka Mountains; in the mountain part of the valley of the Waiohine; the Waingawa and the Ruamahunga; in the Waikanae, the Akaterewa and particularly in the upper part of the Otaki Valley.” Dr. Hector (Trans. N.Z. Inst., vol. ii., p. 379) again refers to the deposit of plumbago at Pakawau, stating that it has probably been derived from an altered portion of a coal seam; and (Trans. N.Z. Inst., vol. x., p. 490) Prof. Liversidge also mentions the occurrence of graphite at Few's Creek, Lake Wakatipu, and Dunstan, Otago—both samples being of an impure nature. During 1878 a sample of graphite shale was forwarded to the Colonial Museum by the Hon. Mr. Acland, as coming from the Malvern Hills; in 1871 samples were forwarded from Wakamarama by Mr. A. J. Burne, which contained from 31.14 to 22.59 per cent. of carbon; in 1876 a graphitic sandstone was forwarded from Jackson's Bay by the Hon. J. A. Bonar, containing 10.42 per cent. of carbon; and in 1878 Mr. McKay collected a very pure sample of graphite, from the Glossopteris beds of Mt. Potts, which contained 90.17 per cent. of carbon, the colour of the ash being reddish. “Although so rich in carbon, it has not that unctuousness which distinguishes the more valuable graphites, but appears indurated and granular defects which must depreciate its value very considerably,“(Lab. Rep. xiii., p 22).

During the same year another sample of graphite was forwarded by Mr. Beere from the vicinity of Wellington, in which the percentage of carbon was 66.71; and Mr. P. C. Cheal also forwarded a very pure sample of graphite from Waiokura Creek, Waimate, Taranaki, the specimen having been found in the bed of a creek. In 1879 Mr. W. Docherty forwarded specimens of mica schist from Dusky Sound, in which scales of graphite were found; and in 1880 Mr. C. W. Tripp sent samples of graphite slate from the Orari Gorge, which contained 20.62 per cent. of carbon. The only samples of this mineral which merit special description are those from Pakawau, Mount Potts, and Waiokura Creek. Graphite.—Pakawau. Compact, with lamellar and petaloidal structure; requires purification to render it of commercial value (Liversidge, Trans. N.Z. Inst., vol. x., p. 490); it is more or less schistose, and varies a good deal as regards purity. Graphite.—Mt. Potts. Finely laminated; black and shining; powder soft, soiling the fingers; hardness about 1, but including small grains which are harder. Does not feel greasy to the touch. Appears to be an intermediate form between anthracite and graphite. Graphite.—Waiokura Creek. A solid compact homogeneous form, separated in distinct laminæ about 1/16 inch thick with siliceous partings at places. Hardness a little over 1. Colour iron-black with black and shining streaks. Mark on paper corresponds with H. pencil. Has only been found as isolated boulders, the enclosing rock being unknown. It is an extremely valuable form of this mineral. Coal.—This mineral is widely distributed throughout New Zealand, but samples from different localities vary greatly in their composition and value as fuel. In 1866 Dr. Hector (First General Coal Report) divided these into Hydrous and Anhydrous coals, or those which still contain a large percentage of water chemically combined with them, and those which we may assume to have been deprived of that water by a chemical change, which, in some cases, may have been induced by causes operating feebly throughout lengthened periods, or, in others, has been rapidly effected on more modern deposits of carbon, under circumstances which favoured a more energetic action. The large number of analyses which were subsequently made of the different classes of coals, together with a careful study of their prevailing characteristics, rendered it necessary to further subdivide them, and in 1872 Dr. Hector (Geological Reports, 1871–72, p. 172) proposed the following classification, which has proved so satisfactory that I cannot do better than adopt it in my present paper:— I. Hydrous (coal containing 10 to 20 per cent. of permanent water.) a. Lignite.—Shows distinct woody structure; laminated or shows that structure on desiccation; very absorbent of water.

b. Brown Coal.—Rarely shows vegetable structure. Fracture irregular, conchoidal, with incipient lamination; colour dark brown; lustre feeble; cracks readily on exposure to the atmosphere, losing 5 to 10 per cent. of water which is not reabsorbed; burns slowly; contains resin in large masses. c. Pitch Coal.—Structure compact; fracture smooth, conchoidal; jointed in large angular pieces; colour brown or black; lustre waxy; does not desiccate on exposure, nor is it absorbent of water; burns freely and contains resin disseminated throughout its mass. a. Glance Coal.—Non-caking, massive, compact or friable; fracture cuboidal, splintery; lustre glistening or metallic; structure obviously laminated; colour black; does not form a caking coke, but slightly adheres. This variety is chiefly brown coal altered by igneous rocks, and presents every intermediate stage from brown coal to anthracite. b. Semibituminous Coal.—Compact, with laminæ of bright and dull coal alternately; fracture irregular; lustre moderate; cakes moderately or is non-caking. c. Bituminous Coals.—Much jointed, homogeneous, tender and friable; lustre pitch-like, glistening, often iridescent; colour black with a purple hue; powder brownish; cakes strongly, the best varieties forming a vitreous coke with brilliant metallic lustre. Hydrous Coals. Lignite.—Deposits of lignite occur widely distributed throughout New Zealand, and in Otago and Southland, as pointed out by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 374); they occur scattered over the surface of the primitive slate rocks of the interior. They are of recent tertiary age, being only overlaid by the newer drifts in the form of brick clays, ferruginous gravels, silts and shingle terraces. One of the most important of these lignite deposits is that near Mataura, in Southland, where a seam from 6 feet to 20 feet in thickness is worked by a number of small open casts for the local requirements of the district, and another important deposit of a similar nature, but from 9 feet to 30 feet thick, is also worked in the interior of Otago at Naseby, Kyeburn, and Hyde. Besides these, many less important deposits of lignite occur throughout New Zealand; thus near Te Anau Lake there are seams about 2 feet thick, and throughout the Lower Waikato basin and near Raglan further deposits occur, some of the outcrops being several feet in thickness, but they are not worked owing to brown coals being more accessible and of better quality. Between

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Napier and Masterton, again, somewhat extensive deposits of the lignite series are met with, in which, however, the seams of lignite are of no great thickness and have received but little attention. Brown Coal.—The principal deposits of brown coal in New Zealand belong to the cretaceo-tertiary formation, and, as pointed out by Dr. Hector (Geol. Rep., 1878–79, p. 7), they are always at the base of the marine portion of the series in every locality where they occur. They always rest upon the basement rock of the district, marking a great unconformity and a long-persistent land area at this period. Thus they are overlaid by the Leda marls in the Waikato, the fucoidal greensands at Whangarei, and by the island sandstone in Otago and on the West Coast of the South Island. They are the most widely-distributed class of coals, being largely represented in Auckland, Canterbury, Otago, Southland, and Nelson. In Auckland the coal from the Waikato is of an inferior character. It does not stand the weather well, and has a high percentage of water. The average composition of these coals is— Fixed carbon 47.08 Hydro-carbon 33.24 Water 17.60 Ash 2.08 100.00 Two mines are at present being worked in these deposits, one, the Huntly Mine, having a seam from 6 feet to 40 feet thick, and the other, the Waikato Mine, a seam from 10 feet to 18 feet in thickness. Besides these, the Bridgewater Colliery, near the Miranda Redoubt, which is now closed, was working a seam no less than 53 feet thick. In Nelson there are a few seams of brown coal, none of which are at present being worked. Amongst these is a highly-inclined seam at Richmond near the town of Nelson, another at Karamea, and at Charleston, near Westport, a large seam of brown coal occurs over a considerable area of flat country, but is not worked since coal of better quality is near at hand. Taking an average of the analyses which have been made of these coals, their composition is as follows:— Fixed carbon. Hydro-carbon. Water. Ash. Richmond 48.82 37.15 9.04 4.99 Karamea 38.90 37.29 16.36 7.45 Charleston 40.82 33.16 21.09 4.93

In Westland no seams of brown coal have been worked, but a few samples have been forwarded from the Grey Coal Reserve, which have the following average composition:— Fixed carbon 46.93 Hydro-carbon 31.13 Water 18.42 Ash 3.52 100.00 In Southland, mines have lately been opened in two seams of coal at the Nightcap Hill above Wairio, in which the composition of the coal is as follows:— Fixed carbon 47.81 Hydro-carbon 21.04 Water 29.24 Ash 1.91 100.00 and another thick seam is known at Orepuki, which will probably be worked as soon as railway communication has been established. It consists of— Fixed carbon 41.21 Hydro-carbon 39.09 Water 11.14 Ash 8.56 100.00 In Canterbury, a valuable series of brown coals exists in the Malvern Hills, which have often been locally altered, in the vicinity of intrusive rocks of later origin, to various stages between brown coals and anthracites. Mines are at present being worked in the unaltered brown coals at Springfield, Smithfield, Canterbury, Homebush, and Lees, in seams from 3 feet to 7 feet 6 inches thick, in which the quality of the coal often varies a great deal even between the top and bottom of the same seam. As an instance of this I may quote the analyses of the top and bottom of the 4.½ feet seam at Springfield, from which it will be seen that the upper part was a glance coal, while the lower had the composition of a very good pitch coal. Top of Seam. Bottom of Seam. Fixed carbon 63.2 47.9 Hydro-carbon 23.6 41.8 Water 3.2 6.3 Ash 10.0 4.0 100.0 100.0

The average of thirteen analyses of the true brown coals from this district give Fixed carbon 42.87 Hydro-carbon 31.89 Water 20.40 Ash 4.84 100.00 as their composition, the fixed carbon varying from 49 to 38 per cent., and the water from 18 to 24 per cent. The coal from the different mines does not vary a great deal in character, for good and inferior samples can be obtained from each. Besides that at the Malvern Hills, there are two seams of brown coal, each 10 feet thick, at the Rakaia Gorge, of which the average composition is— Fixed carbon 45.76 Hydro-carbon 26.62 Water 18.71 Ash 8.91 100.00 and at Mount Somers a seam 25 feet thick occurs, having a composition of— Fixed carbon 39.60 Hydro-carbon 39.20 Water 8.80 Ash 12.40 100.00 In Otago there are brown coals of an inferior character near Oamaru; at the Green Island near Dunedin; and several other localities in which small mines only have been opened to supply local demands. The Green Island Mines, of which there are seven, are working seams of coal from 13 feet to 19 feet thick, and to a great extent supply Dunedin with household fuel. The coals have an average composition of Fixed carbon 40.84 Hydro-carbon 36.57 Water 18.67 Ash 3.92 100.00

At Oamaru the seams of coal are from 6 feet to 25 feet thick, but the output is very limited, the four mines at work having only yielded 3,770 tons during the year 1881. Their average composition is— Fixed carbon 39.76 Hydro-carbon 35.60 Water 17.18 Ash 7.46 100.00 Besides these coals there is an important basin of a better class of brown coals in the Clutha and Tokomairiro districts, as well as at Shag Point, in which several mines have been opened. Of these the Kaitangata Colliery is working a seam 30 feet thick; Eliott Vale, 20 feet; Real McKay 25 feet; and Bruce 12 feet 6 inches. At Shag Point the Shag Point Mine is being worked in a seam 7 feet in thickness. The superiority of these coals over that from Green Island appears to depend upon their having a solid compact roof instead of the loose running sands of the latter locality. Their average composition is— Fixed carbon. Hydrocarbon. Water. Ash. Kaitangata 44.17 38.24 15.42 2.17 Eliott Vale 41.60 35.31 19.48 3.61 Real McKay and Bruce 41.29 40.19 12.37 6.15 Shag Point 43.15 33.70 16.57 6.58 Pitch Coals.—The distinguishing characteristic of these coals is that they do not desiccate on exposure to the air to the same extent as the brown coals, besides which they, as a rule, contain a less proportion of water in combination. They are chiefly met with as seams which overlie the bituminous coals of the west coast of the South Island, where however they have only been worked in the Reefton district and at West Wanganui. They are again met with at Mokau in Taranaki, and at Whangarei. Some of the altered coals of the Malvern Hills, Canterbury, might also be classed with these coals, but since they represent various stages of change from brown coals to anthracites, it is best to group them together under the title of glance coals. The pitch coals of the West Coast may be divided into those from West Wanganui, those from Inangahua, those from the Buller, and those from the Grey districts, of which only the two first have been worked. The seams vary from 2 feet to 10 feet in thickness, and the composition is as follows:— Fixed carbon. Hydrocarbon. Water. Ash. Buller 42.40 36.60 9.20 11.80 Greymouth 40.70 45.61 7.37 6.32 Reefton (Inangahua) 59.54 30.93 9.07 .46 West Wanganui 45.00 39.90 4.80 11.30

At Mokan the coal seams vary from 2 feet to 6 feet in thickness, and a trial of the coal against Waikato showed it to be one-fourth better, 1½ tons of the Mokau coal doing as much as 2 tons of the best Waikato (Hector, Geol. Rep. 1879–80, p. 21). The composition of these coals is– Fixed carbon 52.10 Hydro-carbon 34.00 Water 11.20 Ash 2.70 100.00 At Whangarei two mines are at present at work—viz., Kamo mine, in which there are two seams 4 feet to 4½ feet and 8 feet to 12 feet thick respectively; and the Whau Whau mine, in which the seam is from 5 feet to 9 feet thick; besides which outcrops of coal occur at Whareora 3 feet to 3 feet 6 inches thick; and at Hikurangi, ten miles from Whangarei, there are numerous outcrops of coal from 2 feet to 6 feet thick. The average composition of these coals from a number of analyses is:– Fixed carbon. Hydrocarbon Water. Ash. Kamo 48.83 38.60 8.98 3.59 Whau Whau 47.50 41.45 7.59 3.46 Whareora 45.94 38.79 7.06 8.21 Hikurangi 43.41 45.67 6.16 4.76 making the average analysis of the coals from the Whangarei field— Fixed carbon 46.42 Hydro-carbon 41.13 Water 7.45 Ash 5.00 100.00 Anhydrous Coals. Glance Coals.—These, which are brown coals, altered variously in the vicinity of certain dykes and flöes of dolerite, are only met with as workable seams in the Malvern Hills coalfield, where they occur as seams from 2 feet to 10 feet thick. They occur in all stages of change from brown coals to anthracites, and some of them might, with propriety, be classed under the subdivision of pitch coals, but since they all belong to a series, I have thought it better to group all that have undergone any degree of change under the present head, those in which the percentage of water is high being left with the brown coals. Some of these with a high percentage of water however, exhibit signs of change, the percentage of fixed carbon to hydro-carbon being large, as in the case of the seams at the Rakaia Gorge, already quoted. The following table of analyses shows how varied they are

in composition, and, as previously mentioned, the top and bottom of the same seam will frequently be quite different:— Fixed carbon. Hydrocarbon. Water. Ash. Springfield 47.90 41.80 6.30 4.00 Brockley 49.99 35.22 11.79 2.80 Springfield 50.60 38.80 7.80 2.80 Ayers (thin seam) 52.01 3.69 4.89 39.41 Brockley 53.39 32.04 12.65 2.02 Hill's mine 53.30 33.97 9.98 2.75 Springfield 55.50 30.90 4.20 9.40 Hill's mine 59.39 33.78 3.89 2.94 Williamson's 61.90 26.80 .90 10.40 Kowhai 61.10 35.40 1.60 1.90 Ayers (thick seam) 62.21 18.99 5.20 13.60 Springfield 63.20 23.60 3.20 10.00 Rakaia Gorge 64.51 21.27 6.76 7.46 Acheron 65.80 5.38 4.57 24.25 Kowhai 66.10 14.10 2.20 17.60 Malvern Hills 67.49 17.89 2.12 12.50 Hart's mine 69.62 14.92 2.77 12.69 Malvern Hills 73.94 16.60 3.60 5.86 Kowhai 80.01 10.95 6.50 2.54 Malvern Hills 83.20 12.10 2.20 2.50 Acheron 88.91 12.10 3.17 7.92 Semibituminous Coals.—The only coals of this class of which we know anything are those from the well-known Kawakawa colliery at the Bay of Islands, the output from which for the year 1881 was 50,277 tons, or about ½ of the total quantity of coal raised in New Zealand during that year. The mine is worked in a seam which is from 4 feet to 15 feet thick, and the coal has an average composition of— Fixed carbon 55.59 Hydro-carbon 38.10 Water 4.19 Ash 2.12 100.00 It varies a good deal in its physical characters, being sometimes exceedingly hard and at others quite soft, but the composition is moderately constant. It is an excellent steam coal, and is largely used on the coasting steamers. The same class of coal also occurs at Preservation Inlet in Otago, where it is found in thin impure seams, having the following average composition:— Fixed carbon 61.37 Hydro-carbon 28.06 Water 4.37 Ash 6.20 100.00

Besides which there are numerous small seams, 10 inches thick and less, occurring in the jurassic strata in various localities, as the Hokanui Hills and Mataura, Southland; Waikawa, Otago; and the Waikato Heads, Auckland; in fact wherever the formation occurs, but since they have never been found in seams which are of sufficient thickness to work remuneratively they do not merit any special attention. Bituminous Coals.—These coals are, so far as is at present known, exclusively confined to the west coast of the South Island. At Collingwood they occur as thin seams from 27 inches to 32 inches in thickness; one mine being at present at work in this district. The average composition of the coal from this locality is— Fixed carbon 53.29 Hydro-carbon 38.18 Water 2.06 Ash 6.47 100.00 At Westport seams of bituminous coal occur from 4 feet to 50 feet in thickness, and two mines are at present at work. The estimated quantity of coal in this field, from accurate surveys, is 140,000,000 tons, which is probably considerably below the mark. All the coal is level, free, and generally at an elevation of from 1,000 to 3,000 feet above the sea. The average composition of the coal is— Fixed carbon 63.81 Hydro-carbon 31.88 Water 3.08 Ash 1.23 100.00 There are also two small areas of highly-inclined, faulted coal, which is much crushed, and too tender to be marketable. It has the following composition:— Fixed carbon 75.05 Hydro-carbon 21.29 Water 1.40 Ash 2.26 100.00 Two mines have been opened to work this coal, but both are now abandoned. At Greymouth another series of bituminous coals has been worked in which the percentage of fixed carbon is considerably less than in that from Westport. It is, however, an exceedingly valuable gas coal, and the coke made from it is as good as can be procured. The seams vary in thickness

from 7 feet to 17 feet, those which have been worked hitherto being all 12 feet thick or over. Two mines are at present at work here, but another which has been sold will, it is probable, be shortly at work again, and a new company is being formed to open up another lease. The average composition of these coals is as follows:— Fixed carbon 53.25 Hydro-carbon 38.73 Water 1.48 Ash 6.54 100.00 There is also a small deposit of coal at Kanieri in Westland, of which the composition is— Fixed carbon 47.50 Hydro-carbon 30.17 Water 1.87 Ash 20.46 100.00 and outcrops are also known farther south near the Paringa River, but no work has been expended in opening them up. The question of the evaporative power of the different coals is now receiving the attention of the department, since it has been found that the number which theoretically represents the number of pounds of water which can be converted to steam, by the combustion of a pound of each coal, is only approximately true for the hydrous varieties, giving them a higher theoretical power than in practice they are found to possess. Bituminous Peat.—Chatham Islands. This mineral is described (Col. Mus. and Lab. Reports, iii., p. 11) as follows:— “Colour, black; somewhat vesicular, otherwise very compact; lustre, rather dull generally, bright jet on margins of vesicles. Burns freely to a white ash with much flame; when once set fire to, all the carbonaceous matter is consumed without re-ignition. Does not cake; powder of mineral brown; ash, alkaline; sulphuretted hydrogen cannot be detected in its smoke. Analysis in its normal condition. Analysis after exposure to air until its weight is constant. Fixed carbon 19.87 20.41 Hydro-carbon 64.67 66.43 Water 7.13 4.61 Ash 8.33 8.55 100.00 100.00 Percentage of fixed carbon, deducting water and ash 23.51 Percentage of hydro-carbon, deducting water and ash 76.49 100.00

“This mineral was first discovered by Mr. Traill, occurring in detached masses of irregular form and considerable size in the superficial gravels and peat deposits at most points along the low eastern shore of the Chatham Islands. It appears to have no connection with the brown coal and lignite deposits which occur in the same island; nor could Mr. Traill discover any distinct bed or seam of this mineral. It is very interesting on account of its highly bituminous character, resembling that of the oil-shale found at Mongonui, Auckland.” A similar mineral is found on the Auckland Islands, and is mentioned by Dr. Hector (Trans. N.Z. Inst., vol. ii., p. 183). Bituminous Shale.—A mineral closely approximating to Torbanite is mentioned by Dr. Hector (First Coal Report, 1866, p. 44) as coming from Awatere, near Mongonui, Auckland. It is very coherent, close-grained, hard and tough, almost elastic, does not show the slightest indications of lamina or cleavage planes, having a smooth semi-conchoidal fracture in every direction. Colour, dull black; perfectly homogeneous; powder, brown or chocolate colour; sp. gr. 1.112; ignites with ease and bursts into flame, which is sustained for a long time and with great vigour. Flame at first luminous and bright, but soon becomes long and smoky. During combustion small oil-bubbles are seen escaping. Heated to dull red heat in closed crucible, 23 per cent. of light, non-coherent, cellular and slightly lustrous coke remains, which burns readily in free access of air to a white ash. Analysis. Volatile matter 75.20 Carbon in coke 9.30 Relative percentage Hygroscopic water 1.80 Ash 13.70 Volatile matter 88.99 Sulphur traces Fixed carbon 11.01 100.00 100.00 Carbonaceous Shale.—A mineral having the composition of— Fixed carbon 14.96 Hydro-carbon 39.39 Water 6.74 Ash 38.91 100.00 occurs at Orepuki, Southland, and is reported on (Col. Mus. and Lab. Reports, xi., p. 11), and another from Blueskin Bay, Otago, is also mentioned (Col. Mus. and Lab. Reports, xiii., p. 21), which is composed of— Fixed carbon 13.81 Hydro-carbon 29.78 Water 10.76 Ash 45.65 100.00

These are only hydrous shales containing a certain percentage of carbonaceous matter, and are not of any use for the distillation of oil. Carbonaceous Mineral, Whangarei.—This is described by Captain Hutton (Trans. N.Z. Inst., vol. iii., p. 250) as follows:—“Colour black, with shining resinous lustre; streak and powder, black; very brittle, but does not dirty the fingers. H. about 2. In the flame of a spirit lamp it burns to a white ash without altering its shape, and without giving off any odour or smoke, but it will not burn if taken out of the flame. It appears to be nearly pure carbon without any admixture of bitumen. Dr. Hector gives the following composition for this mineral:— Fixed carbon 34.20 Hydro-carbon 17.00 Water 32.20 Ash 16.60 100.00 from which it appears to be a non-caking lignite approaching jet, burning with difficulty, giving but little flame, and a white ash. Elaterite (Elastic Bitumen), CH2.—The occurrence of this mineral on the coast of the North Island is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 425) as easily impressed by the nail, and perfectly free from any impurities. Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 491) again mentions its occurrence at Poverty Bay, the following being his description of the specimen:—“The exterior surface is of a brown colour, within it is black, burns with a luminous smoky flame, emitting a bituminous odour; leaves a small quantity of white ash; breaks with conchoidal fracture; very brittle; possesses bituminous odour.” It has only up to the present time been found as pieces on the East Coast of the North Island, and on the Island of Kawau, and may possibly not be a natural product, but lost from some ship. Petroleum.—The first mention of this mineral oil is by Dr. Hector (Geol. Rep., 1866–67, p. 4), where he describes its mode of occurrence at Taranaki, and he has also (Geol. Rep., 1873–74, p. xviii.) given a description of the oil-springs at Poverty Bay. Mr. Skey has, in a paper on the mineral oils of New Zealand (Trans. N.Z. Inst., vol. vi., p. 253), given a very good description of their physical characters. 1. Sugar Loaves, Taranaki.—A. very remarkable oil having sp. gr. .960 to .964 at 60° Fahr., dirty green colour by reflected light; opaque, except in thin films, when it has a deep red colour by transmitted light. At 60° Fahr. is quite liquid, and though at lower temperature it has considerable consistency, yet when reduced to 5° Fahr. it does not become solid. Has

a mawkish but not unpleasant odour, being very different in this respect from most rock oils, and is especially free from all traces of sulphuretted hydrogen. Minute flakes of a white substance float in the oil, and are gradually deposited when it is allowed to remain quiet at a low temperature, nearly the whole of this solid substance becoming dissolved when the oil is gently heated. Boils at 340° Fahr., and does not appear to evaporate at ordinary temperatures. Vapour inflames at 260° Fahr.; does not contain paraffin. Very valuable as a lubricant on account of its low freezing and high volatilizing points. 2. Poverty Bay.—A true paraffin oil. Opalescent and thickly interspersed with minute flaky particles of a white colour; by warming the oil gently these particles subside, and the oil manifests the following characters: translucent in masses of considerable thickness; colour, red by transmitted and blackish-green by reflected light; flows readily and gives off the usual odour of crude petroleum. Its boiling-point at 30 ins. barometric pressure varies from 289° to 291° Fahr. The temperature at which the vapour inflames is from 230° to 233° Fahr., and sp. gr. from .864 to .871 at 60° Fahr. Passes into a jelly-like mass at 50° Fahr., owing to the quantity of paraffin dissolved in the oil. 3. Manutahi, Waiapu River.—Is the lightest natural mineral oil known in the colony. Colour, pale brown; nearly or quite transparent; does not manifest a green-black colour by reflected light; flows with great freedom; has the odour of kerosene; sp. gr. .8294 at 60° Fahr.; burns well in a kerosene lamp for some time. Contains only traces of paraffin, and does not acquire any increased consistency when the temperature is lowered to 8° Fahr. For details concerning the constitution of these oils I must refer the reader to the paper above cited, and also to another by the same author (Trans. N.Z. Inst., vol. xi., p. 469). Dopplerite.—A mineral grease resembling dopplerite was collected by Dr. Hector from Waiapu in 1872, and during 1880 a specimen of the same mineral was forwarded to the Colonial Laboratory for examination on the supposition that it was ozokerite or native paraffin. This substance is of a soft greasy nature, brownish-yellow colour, and possesses a strong odour of paraffin. It burns readily with a smoky flame, leaving a large quantity of ash, and consists, according to Mr. Skey (Trans. N.Z. Inst., vol. xiv., p. 398) of 3.1 per cent. oils; 9.3 per cent. paraffin 26.9 per cent. earthy matter; 11.3 per cent. water; and 49.4 per cent. oxygenated hydro-carbons. Ozokerite, Ch.—This mineral is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 267, 438) as occurring in the brown coals of Dunstan, Otago. We have, unfortunately, no specimen of this.

Ambrite (Retinite).—Dr. v. Hochstetter is the first to mention the occurrence of this mineral in New Zealand (New Zealand, 1863; Eng. ed., p. 79). He describes it as follows:—“Fossil resin imbedded in the coal, sometimes in pieces from the size of a fist to that of a man's head, but usually only in smaller groups. It is transparent, very brittle, and has a conchoidal and quite glossy fracture. Colour changes from a bright yellow to dark brown; is easily ignited, much more so than the kauri gum; burns with a steady fast sooting flame, and developes a bituminous rather than aromatic smell. Mr. Richard Maly found as a mean of three chemical analyses of this fossil resin— Carbon 76.53 Computed 76.65 Hydrogen 10.58 " 10.38 Oxygen — " 12.78 Ash .19 " .19 100.00 yelding the formula C32 H26 O4. It shows great indifference to solvents; by friction it becomes electric; H. 2, sp. gr. 1.034 at 12° R. It is sufficiently characterized to deserve a special name, but it comes so near to real amber in composition that it deserves the name of Ambrite.” Dr. Hector also mentions its occurrence (Jurors' Rep. N.Z. Ex., 1865, p. 426) under the name of Retinite, in the brown coals of Hyde, Caversham, Tuapeka, Waitahuna, and Dunstan; and Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 490) again describes samples from Dunstan and the Bay of Islands. It is of common occurrence in the brown coals of New Zealand wherever they occur, being sometimes in moderately large blocks, and at others as dispersed grains. Mellite, AL M3 + 18 H.—A specimen of this mineral was first collected by Captain Hutton from the Thames in 1870, and the specimen is described (Col. Mus. & Lab. Reps., vi., p. 15) as a resinous looking substance, with a splintery fracture. Another specimen was collected by Dr. Hector in 1876 from a cave in Bligh Sound, and is mentioned in the Twelfth Laboratory Report under the number 1913. There is no description and none of the mineral remains. Non-Metallic Minerals.—Class III. Sulphur and Selenium. Sulphur, S.—Considerable quantities of this valuable mineral occur on White Island, where it is deposited from numerous geysers and an enormous boiling spring near the centre of the island (Hector, Jurors' Rep. N.Z. Ex., 1865, pp. 34, 425), and it occurs in smaller quantities on various other islands in the Bay of Plenty. It is also deposited from fumaroles at the Rotomahana hot lakes and Taupo, and in several other localities where hot

springs occur (Hochstetter, New Zealand, 1863, Eng. ed., p. 401). It is found again as an efflorescence on the sulphur sands of lower cretaceous age at Waipara (Haast, Geol. Rep., 1870–71, p. 11), and at various other localities; and the late Mr. E. H. Davis mentions its occurrence (Geol. Rep., 1870–71, p. 131) in Doran's No. 2 Reef, at Wangapeka. Analyses of samples from White Island have given the following results:— Liversidge. Cox. Sulphur 99.614 99.554 98.888 99.9 94.1 63.5 Foreign matter .386 .446 1.112 .1 5.9 37.5 100.000 100.000 100.000 100.0 100.0 100.0 They vary in physical characters from a massive rich sulphur yellow mineral to a loose friable variety with a pale-greenish tinge and some very beautiful, although small, crystals also occur. These are of a pale-greenish colour, and consist chiefly of sharp acicular rhombic prisms; but some very unusual combinations also occur which have been described by the late Mr. E. H. Davis (Trans. N.Z. Inst., vol. iii., p. 284). They are frequently associated with crystals of selenite. Selenium, Se.—Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 491) states that he obtained traces of selenium in the massive yellow variety of sulphur from White Island. Non-Metallic Minerals.—Class IV. Haloids and Salts. {Salts of ammonia, potash, soda, baryta, strontia, lime, magnesia, alumina, yttria, and ceria. Salts of Soda. Glauber Salts, Ńa š + 10 H.—A specimen of this mineral was forwarded for determination by Mr. W. H. Beetham in 1874. The locality of its occurrence is Brancepeth, Whareama, Wellington. Salts of Baryta. Barytes, Ba S.—This mineral was collected by Dr. Hector from Akiteo in 1867, and Mr. Skey mentions its occurrence (Geol. Rep. 1870–71, p. 85) in the auriferous reefs of the Thames. Mr. McKay collected a specimen from Paonui Point, near Napier, in 1874, and specimens have also been received from Te Arai Point, Auckland, and from near East Cape. The following specimens are at present in the collection of the Colonial Museum:— 1. Crystals of Barytes.—Crown Princess Claim, Thames. Of a pure white colour, the largest crystal being about half an inch long. They are of a tabular form, consisting of the prism ∞ P; the brachypinacoid ∞P∞ and the basal pinacoid OP, but in some forms the brachypinacoid is replaced by small faces of the brachydome ∞P∞.

2. Crystals of Barytes.—Thames. A very interesting specimen, consisting of an encrustation of small white transparent crystals, the largest being about ⅛ inch across. These crystals are all tabular, and consist of the prism ∞P (a), the macropinacoid ∞P∞ (b), the brachypinacoid ∞P∞, and the basal pinacoid OP (d), thus forming octagonal plates. In some crystals the macro- and brachypinacoids are developed to the extinction of the planes of the prism, when four-sides tabular plates are formed, and in others again the macrodome ½ P∞ (e) and the brachydome P∞ (f) either bevel the edges of the macro- and brachypinacoid or completely extinguish them, giving rise to the following crystals:— 3. Barytes with Quartz.—Opotiki. A massive variety of a yellowish colour cementing irregular pieces of quartz. This specimen was presented to the museum by the late Rev. Richard Taylor. 4. Radiating Barytes.—Waikouaiti. A specimen presented to the museum by the Hon. W. B. D. Mantell, M.L.C. Witherite, Ba Ċ.—The occurrence of this mineral in some of the mines at the Thames is mentioned by Mr. Skey (Geol. Rep., 1870–71, p, 85), but we have not, unfortunately, any specimen in the museum collection. Salts of Lime. Calcite, Ċa C.—This mineral is so widely distributed in New Zealand in various forms that it is unnecessary to refer to every instance of its occurrence which has been mentioned. Crystallized Calcite.—Dr. Hector mentions its occurrence in the tertiary rocks of Otago (Jurors' Rep. N.Z. Ex., 1865, p. 3), as Dogtooth Spar in limestone at Moeraki, and as Iceland Spar in limestone, marble, etc. (Jurors' Rep. N.Z. Ex., 1865, p. 437); and Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) mentions it in cavities of the volcanic rocks of Canterbury. Professor Liversidge also (Trans. N.Z. Inst., vol. x., p. 491) mentions 16 different specimens of calcite from Dunedin, which are all crystallized as rhombohedrons or combinations of the rhombohedron and scalenohedron. In the Colonial Museum we have the following specimens:— Calcite with Pyrites, Thames.—A massive crystalline variety with rhombohedral cleavage and small rhombohedral crystals in cavity. Colour, white. Calcite with Natrolite, Dunedin.—Small rhombohebral crystals R, and also acute rhombohedrons in cavity in basaltic rock. Colour, pure white and transparent, to dirty grey.

Calcite.—Thames. The terminal end of a large scalenohedron on which an incrustation of small rhombohedral crystals has formed. Calcite with Aragonite.—Seacliff, near Waikouaiti. A number of small obtuse rhombohedron built up, one on the other, giving the whole crystal the appearance of a hexagonal prism with serrated edges, and with terminal rhombohedral planes. It is in a cavity in basalt. Calcite.—Seacliff. A similar specimen to the last, but less perfect. Calcite.—Cape Rodney. A block of white rhombohedral crystals of large size. Smoky Calcite.—Cape Rodney. A slab of beautiful rhombohedral crystals of calcite of a smoky colour. Calcite (Dogtooth Spar).—Tararu Creek, Thames. A large slab of breccia with acute rhombohedral crystals of a pale yellow colour on the face. Massive Crystalline Calcite.—In this form calcite is of common occurrence as veins traversing many different sorts of rocks. It notably occurs in the slate of the Tokatea Range at Coromandel, and in the mines of the Thames, where, owing to its decomposition in contact with acids, the carbonic acid gas is formed which is found in such large quantities at the lower levels of the mines, sometimes rendering futile all attempts at ventilation. It is also frequently met with as large veins in the Maitai limestone of lower carboniferous age both in Nelson and Otago, and again associated with the crystalline marbles of the West Coast and Collingwood. It has also been found, under most interesting circumstances, in some of the granites of the West Coast Sounds, where it occurs as large rhombohedral masses entering into the composition of the rock as an accessory mineral. Marble.—Some very fine deposits of marble occur in New Zealand, in Caswell and Milford Sounds on the West Coast, as mentioned by Dr. Hector (Report of Explorations of West Coast of Otago, “Provincial Gazette” and Jurors' Rep. N.Z. Ex., 1865, p. 3), and in the former locality a quarry has been opened out by a newly-formed company. The better varieties are of a pure white colour and saccharine texture; they are reported by Mr. McKay to occur moderately free from joints, and to be obtainable in large blocks (Geol. Rep., 1880–81, p. 115). There is also a coarser crystalline variety, as well as a black-veined marble, which occurs in considerable quantities. Marble of good quality again occurs at Colling-wood and on the Riwaka Range between Takaka and Motueka, and a crystalline limestone, frequently called marble, is also found associated with the lower carboniferous rocks, and is met with in Nelson; the Blue Mountains, near Palmerston, Otago; and in the Clent Hills, Canterbury.

Madrepore Limestone.—At Reefton a limestone occurs, chiefly composed of large madrepore corals, which if cut and polished would afford a most beautiful ornamental stone. Lithographic Limestone.—A stone suitable for most classes of lithographic work has been found in considerable quantities at the Abbey Rocks, West-land, and again at Amuri Bluff; but at the latter locality it is too much traversed by joints to be of any value. Chalk.—Dr. Hector mentions (Trans. N.Z. Inst., vol. ii., p. 178) the occurrence of chalk with flints on Campbell Island, and during 1880 a deposit of chalk, not less than 100 feet thick, was discovered at West Oxford, Canterbury, of which Dr. Hector says (Geol. Rep., 1879–80, p. xviii.): “The samples of chalk obtained have more perfectly the mineral character and texture of English chalk than any previously discovered in New Zealand. The rock is pure white, fine-grained, and soft enough to be used for the manufacture of crayons. “Its composition as determined by analysis is as follows:— Calcic carbonate 82.36 Magnesic carbonate 1.84 Ferric oxide traces Silica 15.69 Water 0.21 100.00.” Stalactites and Stalagmites occur in all the many limestone caves of New Zealand, some of them being of great size and beauty. Of these the caves at Whangarei, Waipu, Collingwood, and Mount Somers are well known for the variety in form and size in which these deposits of lime occur. Travertine.—Dr. v. Haast mentions (Jurors' Rep. N.Z. Ex., 1865, p. 256) a deposit of travertine from calcareous waters at the Weka Pass, and it occurs on a small scale in many localities, but no large deposits are known.** A remarkable deposit of this mineral occurs on the Alfred River, a branch of the Maruia River, in terraces which are in the aggregate about 400 feet in height. They are chiefly composed of moss which has been petrified by the calcareous waters, and are now partially clothed by a fresh growth of this moss. Limestone occurs very widely distributed throughout New Zealand in all degrees of purity and texture from a marl with 4 or 5 per cent. of carbonate of lime to a limestone which is nearly pure. Hydraulic varieties also exist, and at Mahurangi a deposit of this sort has been worked for some time past. Aragonite, Ċa C, is by no means of so common occurrence as calcite, but has still been found in a few localities. Dr. Hector mentions it (Jurors' Rep. N.Z. Ex., 1865, p. 266) in cavities in basaltic rocks at Dunedin, and

Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p, 256) states that it occurs lining fissures and cavities in the volcanic rocks of Banks Peninsula. In 1869, Capt. Hutton collected specimens from the Eldorado claim, Thames; in 1870 a specimen with calcite was forwarded from Oamaru by Mr. Traill; in 1875 Mr. McKay collected specimens from Whangaroa North, and in 1877 another from Waitaki. Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 493) describes four specimens from Dunedin, three of these being in amygdaloidal cavities, associated with calcite, and corresponding with the specimen I collected from Seacliff (mentioned under calcite, p. 381); the fourth being rosettes of pale yellow-coloured prisms. The acicular crystals of carbonate of lime mentioned by Dr. Hector (Handbook of N.Z., Melbourne Exhibition, 1880, p. 108) as deposited from a hot spring at Waipiro are also probably aragonite. The specimens in the Colonial Museum are:— 1. Crystals of Aragonite.—Eldorado Claim, Thames. A pure white transparent variety in prismatic crystals, consisting of the prism ∞P, the brachypinacoid ∞P∞, and the brachydome P∞. 2. Crystals of Aragonite.—Quartz hills, Collingwood. These include a large collection which I made during the summer of 1880, some of the groups of crystals being of exceeding beauty. They occur under somewhat unusual circumstances, having crystallized in small recesses about a foot deep in an isolated patch of limestone which occurs there. They consist chiefly of rhombic prisms, macled along a face of ∞P. They sometimes assume a more or less radiate form, but far more frequently interlace, forming a most beautiful network of fine acicular crystals. In some cases again they occur as little tufts of cream-coloured crystals about half an inch in diameter, and again as small bunches of acicular crystals, which are frequently terminated by very small stalactites. They are generally of a pale cream colour, but in some cases are brown, owing to the presence of ferric oxide. Gypsum (Selenite), Ċa S + 2 H.—This mineral occurs in several localities in New Zealand, either in groups of crystals associated with sulphur, as on White Island, where it also occurs in a massive form with sulphur disseminated through it; or as nests of crystals in clay or marl, as at Moeraki and Waihao. The first mention of it in New Zealand is by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 35, 266, 422, and 437), who states that it is found crystallized in clay at Moeraki, and also in lenticular masses at the same locality. It is again mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) occurring as crystals on the surface of tertiary shales at Tenawai. Dr. Hector also mentions the occurrence of gypsum (Trans. N.Z. Inst., vol. ii., p. 367) in the auriferous rocks of the Thames (Trans. N.Z. Inst., vol. iii., p. 278), at White Island (Geol. Rep., 1873–74, pp. xii. and xviii.) in the sulphur sands of Amuri Bluff and the

black shales of the Awanui series at Poverty Bay; Mr. Skey (Goel. Rep., 1870–71, p. 88) mentions its occurrence at the Thames; Dr. v. Haast (Geol. Rep., 1873–74, p. 18) as crystals in dark greyish sands at Lake Heron; and Mr. McKay (Geol. Rep., 1880–81), at Waihao River, Canterbury. Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 493) has described some rough crystals from Moeraki and Awamoko, and thin, columnar, opaque white crystals, sometimes interlacing and somewhat fibrous, from White Island, as well as a white opaque mammillated encrusting mass from a cave at Mr. Nicholas', Lake Wakatipu. Besides these, specimens have been forwarded for identification from the Malvern Hills by Mr. H. H. de Bourbel, from the Kaitoki Ranges, New Plymouth, by Mr. Robert Hughes, and the Thames by Mr. McDonald. The specimens in the Colonial Museum are chiefly from White Island (from which locality a very beautiful collection has been made by Dr. Hector), and from Waihao, Canterbury. Dr. Hector has described those from White Island as follows (Trans. N.Z. Inst., vol. iii., p. 284):—“The specimens obtained from the edge of the lake are chiefly masses of sulphate of lime, sometimes in the form of massive gypsum, but more frequently crystallized in the form of oblique prisms of selenite. The faces of these crystals are frequently coated with crystalline films of pure sulphur.” The specimens from Waihao are transparent crystals of selenite roughly crystallized and imbedded in clay-shale. They occur chiefly as crystals, consisting of the prism ∞P., the clinopinacoid ∞Pc∞, and the hemipyramid -P; and they are frequently macled, along a face parallel to the orthodiagonal, to form rough arrow-head crystals, sometimes of considerable size. They are sometimes arranged in stellate groups. A specimen has also been collected from Tohatapu, in the Otamatea arm of Kaipara Harbour, where it occurs as opaque white plates imbedded in a sandy marl. Apatite, 3 Ċa3 P + Ca (Cl, F).—This mineral is mentioned by R. Daintree, Esq., F.G.S. (Trans. N.Z. Inst., vol. vii., p. 459), as slender acicular crystals occurring in dolerite from the Hororata district, and as long prisms in dolerite from the Acheron section. Salts of Magnesia. Magnesite, Mg C.—A soft, white, earthy variety of this mineral is in the collection of the geological survey from Rotorua, and a nearly pure, white, massive form has also been collected by Mr. S. P. Smith from the Chatham Islands. In 1878 I collected a crystallized specimen from Collingwood, in which the rhombohedral cleavage is very perfect, colour white, lustre pearly.

Dolomite, Ċa Ċ + Mg Ċ.—Dr. v. Haast mentions the occurrence of this mineral at the Malvern Hills (Jurors' Rep. N.Z. Ex., 1865, p. 256) interstratified with augitic greenstone, and it was collected by Dr. Hector in 1872 from Collingwood. Pearlspar.—A specimen of this mineral was collected by Dr. Hector in 1878, from the Big Pump Shaft at the Thames. Epsom-salt, Mg S + 7 H.—Dr. Hector mentions the occurrence of this mineral on Murison's station in Otago (Jurors' Rep. N.Z. Ex., 1865, p. 438). Salts of Alumina. Taranakite.—This mineral, which is a double hydrous phosphate of alumina and potash, part of the alumina being replaced by ferric oxide, was first discovered by H. Richmond, Esq., at the Sugar Loaves, Taranaki, where it occurs as thin seams which occupy fissures in the trachytic rocks. It is described by Dr. Hector (Juror's Rep. N.Z. Ex., 1865, p. 423) as of a yellowish-white colour; amorphous and soft; readily fusible before the blowpipe, and in other respects resembling wavellite. It has the following composition:— Phosphoric acid 35.05 Alumina 21.43 Ferrous oxide 4.45 Lime .53 Potash .4.20 Soda traces Chlorine .46 Sulphuric acid traces Insoluble in acid(silica) .80 Waterdrivenoff at 212° 15.46 33.06 """ red heat 17.60 100.00 and has a slight acid reaction. Wavellite, AL3 P2 + 12 H.—Occurs as thin seams of a dark, yellowish-brown colour, hard, translucent, and infusible, traversing the taranakite in various directions, and is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex. 1865, p. 424). Alunogene, AL S3 + 18 H, is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 438) as occurring in some of the brown coals. In 1867 a specimen was forwarded from Tuapeka by Dr. Halley, which proved to be nearly pure sulphate of alumina. It was colourless and well crystallized and completely soluble in water. The following analysis shows that its composition is— Sulphate of alumina, with traces of sulphate of lime 55.60 Sulphate of lime 1.01 " magnesia 2.99 Alkaline sulphates 3.00 Water 37.40 100.00

In 1868 a specimen, also consisting chiefly of sulphate of alumina, was forwarded for identification by Mr. G. Richardson from Rancowers Island, Manawatu. Alum, R S + (AL Fe) S3 + 24 H.—The first mention of the occurrence of this mineral in New Zealand is by Dr. v. Hochstetter (New Zealand, 1863, Eng. ed., p. 408), who states that on Puai Island, in the Rotomahana Lake, he found films of fibrous alum under cakes of siliceous deposit. Dr. Hector mentions its occurrence as a product of decomposition of pyritous shale at Waikouaiti (Jurors' Rep. N.Z. Ex., 1865, p. 35), and (p. 421) he states that aluminous shale is generally associated with the brown coal formation. An analysis of some shale that had undergone natural decomposition, and was covered with an efflorescence of alum, gave— Sulphateof alumina 11.80 ""protoxide of iron 5.27 "" sesquioxide of iron traces "" lime 1.31 ""soda and potash 14.60 Chlorides traces Insoluble in water 33.30 Water and loss 33.72 100.00 the insoluble matter being principally angular fragments of schist. He also mentions (Jurors Rep. N.Z. Ex., 1865, p. 438) the occurrence of potash alum in shale at Tokomairiro, and the Auckland Local Committee exhibited specimens of alum from Rotomahana. In 1866 Mr. T. R. Hacket collected some magnesian alum from D'Urville Island, where it is found as delicate acicular crystals, of a pure white colour, grouped in large botryoidal masses, the exterior surfaces of which are of a yellowish colour from the presence of basic sulphate of iron. It has a sour and slightly astringent taste, is very soluble in water and intumesces on the application of a gentle heat. In the blowpipe flame after desiccation it is infusible; displays considerable incandescence and yields the reaction of soda. Its composition is— Alumina 10.40 Ferric oxide 1.11 Lime .50 Magnesia 5.46 Soda .41 Sulphuric acid 37.40 Hydrochloric acid traces Water 42.72 Insoluble in water 2.00 100.00

Non-Metallic Minerals.—Class V. Earths (Silica and Alumina). Silica. Quartz, Si.—The distribution of this mineral in New Zealand in one form or the other is general. Rock Crystal.—The purest form of quartz is represented in the collection of the Colonial Museum by a clear pellucid specimen from Tamata, and some beautiful little crystals from Kereru, Napier, which were forwarded on the supposition that they were diamonds. These small rock crystals occur in many localities in the North Island, being derived from the rhyolitic rocks, which occupy a considerable area in the Taupo district; and they are again found in Canterbury, where they enter into the composition of the quartz porphyries of Mt. Somers and the Clent Hills; they have frequently been forwarded for examination from time to time on the supposition that they were diamonds. Some very beautiful specimens of rock crystal were collected from the Cromwell Company's Mine last year by Mr. McKay, the crystals being sometimes three-quarters of an inch long and a sixteenth of an inch in diameter, the ends being sometimes pyramidal, sometimes hemihedral, and sometimes tetrahedral; they frequently interpenetrate one another, and two groups of crystals interpenetrate and pass through very flat and perfectly crystallized rhombohedrons of calcite. Some fine specimens from Milford Sound are also in the collection. Amethyst Quartz.—Some very fine specimens from the Rakaia Gorge, Canterbury, are in the collection of the Colonial Museum, and Dr. v. Haast mentions its occurrence in amygdaloidal trap (Jurors' Rep. N.Z. Ex., 1865, p. 256) and in the melaphyres of Canterbury (Geol. Rep. 1873–74, p. 9). Milky Quartz.—Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) mentions it in the granites of the West Coast, and it is of common occurrence throughout New Zealand. Prase is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) as small deposits in quartzose porphyritic trachytes at the Gawler Downs. Jasper.—There is in the collection of the Colonial Museum a specimen from Tinker's Gully, Thames, which is red but gritty, one from Hongikuri, Auckland, also red but gritty, and another from Mahurangi, which is red, with opaline and brown patches. Besides these Dr. Hector has mentioned its occurrence at the Snares (Trans. N.Z. Inst., vol. ii., p. 177), in the volcanic rocks of Moeraki and Otepopo, and the porphyritic rocks of Dunedin Harbour (Jurors' Rep. N.Z. Ex., 1865, pp. 266 and 437), and at Coromandel and Whangaparawa (Jurors' Rep. N.Z. Ex., 1865, p. 253); it is mentioned by Dr. v. Haast from the Malvern Hills (Jurors' Rep. N.Z.

Ex., 1865, p. 256), and as porcelain jasper from Petrifying Gully, Mount Somers (Geol. Rep., 1873–74, pp. 9, 10); by Dr. v. Hochstetter in the tuffs and conglomerates of Coromandel (New Zealand, 1863, Eng. ed., p. 96); by Mr. J. C. Crawford, at Ruamahunga (Trans. N.Z. Inst., vol. ii., p. 345), and by Prof. Liversidge at Clutha, and as green jasper at Moeraki (Trans. N.Z. Inst., vol. x., p. 496). He describes the specimen from Moeraki as follows:—“Variegated with reddish brown streaks; a little chalcedony on one surface. The green colour is mainly due to the presence of protoxide of iron; there is also manganese present in small quantity. On heating in a closed tube it decrepitates slightly, blackens and gives off water having an alkaline reaction; there is a slight empyreumatic odour evolved.” Mr. Buchanan has also mentioned the occurrence of green jasper at the Awatere River (Geol. Rep., 1866–67, p. 35), and Captain Hutton alludes to it near Hongikuri on the Cape Colville Peninsula, where rounded blocks of diorite are encased with a coating of red jasper (Geol. Rep., 1867, p. 8). Lydian Stome.—A specimen of grey flinty slate from Whangarei is in the collection of the Colonial Museum, and lydian stone is also mentioned by Dr. v. Haast, at the Malvern Hills. (Jurors' Rep. N.Z. Ex., 1865, p. 256.) Chert and Quartzite are of very frequent occurrence in our metamorphic rocks and silurian beds; they occur as thick beds in the Lower Devonian formation, where they are fossiliferous; are met with again in the Lower Carboniferous and Upper Devonian series; and again in many of the Lower Secondary and Jurassic rocks, where they sometimes occur as fossiliferous beds. Flint occurs in chalk at Oamaru, in chalk marls at the Kaipara and Bay of Islands, and as black and grey masses in Petrifying Gully, Mt. Somers, where also iron flint of a red and brown colour is found. It is mentioned by Dr. Hector in chalk on Campbell Island (Trans. N.Z. Inst., vol. ii., p. 178), and by Dr. v. Haast as filling cavities in the rocks of Canterbury (Jurors' Rep. N.Z. Ex., 1865, p. 256), and in the limestone of Amuri Bluff, (Geol. Rep., 1870–71, p. 38), and Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 495) mentions its occurrence at Tapanui, Otago, and Whangarei Heads, Auckland. Chalcedony.—This mineral has chiefly been found in geodes in the melaphyres and quartz-porphyries of Canterbury, but the specimens are chiefly of an inferior class. They are green, grey, brown, and white, and are sometimes arranged in parallel bands passing into agate or onyx. In the collection of the Colonial Museum, there are specimens from Clent Hills, Gawler Downs, Mt. Somers, and Tokatoka on the Wairoa River. It is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) in the volcanic rocks of Moeraki and Otepopo; by Dr. v. Haast (Jurors'

Rep. N.Z. Ex., 1865, p. 256) in mammillated and botryoidal forms in amygdaloidal traps and quartzose trachytes, Canterbury; and by Dr. v. Hochstetter (New Zealand, 1863, Eng. ed., p. 96) in the tuffs and conglomerates of Coromandel; agates being mentioned from the same localities and onyx by Dr. v. Haast from the Malvern Hills, Clent Hills, Mt. Somers, etc. Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 494) mentions the occurrence of chalcedony at Moeraki and Otepopo, and agate at Mt. Charles, Otago. Carnelian is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) in the volcanic rocks at Moeraki and Otepopo, and the porphyritic rocks of Dunedin Harbour; by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) in small geodes in the volcanic rocks of Canterbury; and by Dr. v. Hochstetter (New Zealand, 1863, Eng. ed., p. 96) in the tuffs and conglomerates of Coromandel; and Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 495) describes two inferior specimens from Coromandel. Plasma.—There are four specimens of this mineral in the collection of the Colonial Museum from Mt. Somers and Gawler Downs. They are of a pale to dark leek green and waxy lustre. It is also mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 266) in the volcanic rocks of Moeraki and Otepopo; and by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256), filling fissures in tertiary quartzose trachyte at Gawler Downs. Chrysoprase is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) filling cavities in amygdaloidal rocks in Canterbury. Bloodstone.—There is one inferior specimen in the collection of the Colonial Museum from Clent Hills. It is of a deep green colour with small red spots. Dr. v. Haast mentions its occurrence in small pieces at Snowy Peak and Malvern Hills. Quartz as Pseudomorphs of Calcite.—There is a specimen of quartz from the Malvern Hills in the collection of the Colonial Museum forming hollow pseudomorphs of rhombohedral crystals of calcite, some of the calcareous crystals being still preserved, and Dr. Haast also mentions the occurrence of a similar mineral at Rakaia Gorge and Clent Hills (Jurors' Rep. N.Z. Ex., 1865, p. 256.) Quartz Sands.—Heavy deposits of quartz sand in various degrees of purity occur associated with the lower beds of the cretaceo-tertiary formation at Mt. Somers, Limestone Bluff on the Ashburton River, Lake Heron and Waipara, as mentioned by Dr. v. Haast (Geol. Rep., 1870–71, p. 11; and 1873–74, p. 17.) Tridymite, Si.—Small hexagonal plates of tridymite occur in the trachytic rocks of Lyttelton Harbour, and were first recognized by Professor Ulrich in specimens collected by Dr. v. Haast.

Opal, Si, H, or Si H3.—The more valuable varieties are not known in New Zealand, but the inferior qualities are of common occurrence. Hyalite is mentioned by Dr. v. Haast as occurring in small masses, lining cavities in the volcanic rocks of Snowy Peak and the Malvern Hills (Jurors' Rep. N.Z. Ex., 1865, p, 256), and again in a few localities in the volcanic rocks of Banks Peninsula (Trans. N.Z. Inst., vol. xi., p. 511), and is also mentioned by Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 496) lining cavities in the vesicular grey trachytes of Bell Hill, Dunedin. Common Opal and Semi-opal are mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 256) as filling small cavities in the quartz porphyries of the Malvern Hills and Mt. Somers, and last year I obtained from the drift of Owharoa a specimen which is of a pure milky-white colour. Wood Opal (Silicified Wood) is very common where siliceous rocks are decomposing as at Petrifying Gully, Mount Somers. It is mentioned by Dr. v. Hochstetter (New Zealand 1863, Eng. ed., p. 96) in the tuffs and conglomerates of Coromandel, and by Dr. Haast (Juror's Rep. N.Z. Ex., 1865, p. 256) from many localities in Canterbury. Pitch Opal.—A specimen from Dunstan is described by Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 496) as follows:—“Brown, variegated, light and dark shades. Hardness about 6. When heated in closed tube gives off water, blackens, and emits empyreumatic odour; the condensed water has an acid reaction, and on evaporation leaves a carbonaceous residue which blackens on ignition; breaks with a well-marked conchoidal fracture; contains iron.” There are two specimens of this mineral in the collection of the Colonial Museum—one from the Harper Hills, and the other from the Rakaia Gorge. Opal-jasper.—There is in the collection of the Colonial Museum a specimen of opaline quartz with jasper, from the trachyte tufa of Portobello, Otago, which forms a very pretty ornamental stone. The predominating colours as described by Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 496) are red-brown, blue-grey, and opal-white. Siliceous Sinter.—Deposits of this class are found surrounding several of the thermal springs, and have been well described by Dr. v. Hochstetter (New Zealand, 1863, Eng. ed., pp. 398, 412). He says, in speaking of the siliceous deposits of Orakeikorako: “The sediment of this, like all the surrounding streams, is siliceous; the recent sediment is soft as gelatine, gradually hardening into a triturable mass, sandy to the touch, and finally forming, by the layers deposited one above the other, a solid mass of rock of very variable description at different places both as to colour and structure. Here it is a radiated fibrous or stalky mass of light brown colour; there a chalcedony hard as steel, or a grey flint; at other places the deposit

is white, with glossy conchoidal fracture like milk-opal, or with earthy fracture like magnesite. At Te Tarata siliceous deposits in terraces cover about three acres of land. Alumina. Corundum, Ä l.—Dr. v. Haast mentions the occurrence of the variety sapphire from the western slopes of the Southern Alps (Geol. Rep., 1870–71, p. 94), and in August, 1871, Captain Hutton brought another specimen from Collingwood, which is now in the Colonial Museum. It is described in the Seventh Museum and Laboratory Report, p. 18, as follows:—“A tough sapphire, sent by a digger, who found it with alluvial gold at Collingwood, Nelson, is the first discovery of this precious stone in the colony. The specimen, which weighs 336.9 grains, is in the form of a water-worn pebble, remarkable on account of its deep blue colour on the fractured surface, and its great weight; but it is so traversed by fissures as to be of no value as a gem. Its specific gravity is 3.869.” Non-metallic Minerals.—Class VI. Silicates and Aluminates.} Silicates of magnesia and lime, hydrous and anhydrous. Silicates of alumina, hydrous and anhydrous. Aluminates of magnesia and glucina. Silicates of glucina, zirconia, thoria, and yttria. Anhydrous Silicates of Magnesia and Lime. Wollastonite, Ċa Si.—Specimens of a massive form of wollastonite were collected from the Dun Mountain by the late Mr. E. H. Davis in 1871, and are now in the collection of the Colonial Museum. They have been described and analyzed by Mr. Skey, who reports (Col. Mus. & Lab. Rep. vi., p. 15) that the four specimens examined had the following composition:— 1. 2. 3. 4. Silica 48.01 49.30 50.62 58.80 Lime 46.20 45.91 44.83 24.60 Magnesia traces .80 traces 1.60 Alumina 1.45 1.41 1.84 12.20 Iron oxide traces traces 1.64 {12.20 Loss 2.19 1.19 traces 1.40 Water 2.15 1.39 1.02 1.40 100.00 100.00 100.00 100.00 The iron oxide in Nos. 3 and 4 is the protoxide, and No. 4 contains traces of chromium. They are massive, confusedly crystalline, colour pure white, lustre pearly inclining to vitreous on certain fractures, easily fusible to glassy bead with no soda reaction. Easily decomposed by hydrochloric acid with the formation of gelatinous silica; hardness 4 to 5. No. 4 is an impure

wollastonite passing into scapolite by substitution of alumina for lime. It is a green-coloured mineral, quite amorphous, and occurs coating one side of a tough light green rock, probably jade. Chrysolite (Olivine), (Mg,Fe)a Si.—The first mention of the occurrence of this mineral in New Zealand is by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 418, and 437), who states that it is of frequent occurrence in the basaltic rocks of Saddle Hill and elsewhere, and also occurs in Milford Sound. It is again mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257) as grains in the basaltic rocks of Banks Peninsula, and (Trans. N.Z. Inst., vol. i., p. 180) as large concretions in basaltic rocks from the Chatham Islands, and (Geol. Rep., 1870–71, p. 29) in the basalts of the Hurunui and Mandamus districts. R. Daintree, Esq., F.G.S., refers to its occurrence in dolerites from the Selwyn River, Snowy Peak Range, Flagstaff Hill basin, and Hororata district, (Trans. N.Z. Inst., vol. vii., p. 458); Professor Liversidge also describes a specimen from Dunedin as brown-coloured imbedded grains (Trans. N.Z. Inst., vol. x., p. 497), and I have noticed small grains of this mineral, green and brown in colour, in many microscopic sections of basaltic and doleritic rocks from various localities. Dunite.—This mineral is a massive variety of olivine through which grains of chromite are scattered. A specimen from the Dun Mountain, Nelson, was first described by Dr. v. Hochstetter (New Zealand, 1863, Eng. ed., p. 474) as follows:—“It consists of a very peculiar kind of rock, of a yellowish-green colour when recently broken, but turning a rusty brown on the surface when decomposing. The mass of the rock is olivine, containing fine black grains of chromate of iron interspersed; it is distinguished from serpentine, for which it was formerly taken, especially by its greater hardness and its crystalline structure. I have called it Dunite.” Analysis of dunite by R. Renter (Lab. of the Polyt. Inst. of Vienna):— Silica 42.80 Magnesia 47.38 Protoxide of iron 9.40 Water .57 Sp. gr. 3.30 100.15 It is again mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 411), who adds to Dr. v. Hochstetter's description, that it possesses a flaky structure, conchoidal fracture and hardness of 6; and he also mentions its occurrence at Milford Sound, where it passes into jade. He again alludes to it (Trans. N.Z. Inst., vol. ii., p. 377), stating that at the Dun Mountain it appears at the surface as a large mass several miles in extent. It has since been discovered at Jackson's Bay, by Mr. D. Macfarlane, associated with serpentinous rocks (Geol. Rep., 1876–77, p. 27).

Augite, R Si = (Ċa, Mg, Fe) Si.—This mineral enters into the composition of all our basalts, dolerites, anamesites, trachydolerites, diabases, and melaphyres. Isolated crystals are rare, but there is a specimen in the collection of the Colonial Museum, of porphyritic diabase from Nelson, in which dark-green monoclinic crystals of augite are well developed, some of them being half an inch long. No macles are seen in this specimen. It is mentioned by Dr. Hector in the basalts around Dunedin (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 438), in basalt from the Snares, and in dolerite from Antipodes Island (Trans. N.Z. Inst., vol. ii., p. 179), and in the dolerites and basalts of the Auckland Islands (Trans. N.Z. Inst., vol. ii., p. 183); by Dr. v. Haast in trachydolerites and as fine twin crystals imbedded in agglomeratic tufa, Banks Peninsula (Jurors' Rep. N.Z. Ex., 1865, p. 257), in concretions in basaltic rocks of Chatham Islands (Trans. N.Z. Inst., vol. i., p. 180), and in basalts of Banks Peninsula (Trans. N.Z. Inst., vol. xi., p. 499); and by R. Daintree, Esq., F.G.S., in dolerite from the Selwyn River, Snowy Peak Range, Hororata District, Flagstaff Hill basin and Acheron section. Asbestos.—The occurrence of this mineral at Milford Sound is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 266), and the late Mr. E. H. Davis records it from Dun Mountain (Geol. Rep., 1870–71, p. 112). There are several specimens in the collection of the Colonial Museum, but none of them possess that flexibility and readiness to separate into fibres without which the mineral is of but little value. The best sample was collected from Collingwood by Dr. Hector; it is of a pale green colour and fibrous. It occurs associated with the steatites there. Tachylite, Äl Sia + 3 (Fe, Ċa, Mg, Mn, Na, K) Si.—The occurrence of this mineral on the sides of fissures in the volcanic rocks of Banks Peninsula, where trachytic dykes have intruded, is mentioned by Dr. v. Haast (Trans. N.Z. Inst., vol. xi., p. 503). Hornblende, R Si.—Is of very common occurrence in New Zealand as a constituent of the syenites, trachytes and diorites which abound, and also in certain hornblendic schists and gneiss which are met with in the northwestern part of the South Island, and again at the Bluff, Southland. It is mentioned by Dr. v. Hochstetter (New Zealand, 1863, Eng. ed., p. 471) as a blackish-green hornblende in the syenite of the boulder-bank, Nelson; by Dr. Hector as veins in syenitic and older trap-rocks in Milford Sound (Jurors' Rep. N.Z. Ex., 1865, pp. 267, 438), in the trachyte of the Sugar Loaves, Taranaki (Geol. Rep., 1866–67, p. 8), as a hornblende rock in the Auckland Islands and Ruapuke (Trans. N. Z. Inst., vol. ii., pp. 183, 185), and in diorite on Great Barrier Island (Trans. N.Z. Inst., vol. ii., p. 375); by Dr. v. Haast, in basaltic and doleritic rocks at Banks Peninsula, Malvern

Hills, Timaru, etc., (Jurors' Rep. N.Z. Ex., 1865, p. 257, and Trans. N.Z. Inst., vol. xi., p. 499), probably only in very small quantities as an accessory mineral, or the rocks would necessarily become andesites, and as large concretions in basaltic rocks of the Chatham Islands (Trans. N.Z. Inst., vol. i., p. 180); by Mr. Buchanan, as fine specimens with serpentine from the Awatere River (Geol. Rep., 1866–67, p. 35); by Mr. E. H. Davis, at Dun Mountain (Geol. Rep., 1870–71, p. 112); and by Prof. Liversidge, at Lake McKerrow, West Coast, Kakanui Mountains, Dun Mountain, and Dunedin (Trans. N.Z. Inst., vol. x., p. 496), besides which there are some fine specimens in the collection of the Colonial Museum from syenitic gneiss of the Baton River, Nelson. Tremolite.—Some beautiful dendritic groups of tremolite, in quartzite, from Kanieri, Hokitika, of a dark green colour, are in the collection of the Colonial Museum, as well as some fine greenish-white radiating crystals from Parapara, Collingwood, and some bright green radiating crystals from the same locality. The occurrence of the mineral in Milford Sound is also mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 267, 438). Actinolite.—The occurrence of this mineral in New Zealand is noted by Dr. v. Haast in metamorphic schists of the West Coast (Jurors' Rep. N.Z. Ex, 1865, p. 257); by Mr. Buchanan in the Awatere River (Geol. Rep., 1866–67, p. 35); and by myself as radiating fan-shaped crystals in the river-beds of the West Coast south of Mt. Cook, where they are much decomposed (Geol. Rep., 1874–76, p. 73). Anthophyllite.—Specimens of this mineral have been collected from the Dun Mountain from time to time, the first specimens having been brought by Mr. E. H. Davis in 1871. It occurs in a massive laminated form of a leek-green colour, with a pearly lustre and a faint bronze hue on the cleavage planes. Nephrite, R Si.—The occurrence of this mineral, commonly known as “Maori greenstone,” is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 412, 437)**The first notice of this and the other Otago minerals is to be found in Dr. Hector's reports on the geology of Otago, published in the Provincial Government Gazette for 1862–64, but these being now difficult of access, the reference (Jurors' Rep. N.Z. Ex., 1865) has been adopted throughout this paper, as in that publication Dr. Hector included a list of all minerals which had been noted in his reports up to that date. from Milford Sound, and also as a single rolled fragment, which had probably been carried there, from Silverstream, Dunedin; by Dr. v. Haast (Jurors Rep. N.Z. Ex., 1865, p. 257) as rolled pieces on the beach of the West Coast; and by the late Mr. E. H. Davi (Geol. Rep., 1870–71, p. 112) as white nephrite from Dun Mountain. The only locality where it has been found in sitú is at Milford Sound, where it

occurs as veins traversing serpentine and hornblende schist, one variety being speckled with chromic iron. It is found as boulders, sometimes of great size, in the auriferous wash of a few localities on the West Coast, such as the Kumara diggings, on the banks of the Teremakau River, and the Greenstone diggings near Lake Brunner. Two analyses of this mineral, quoted by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 413) give the following composition:— Silica 51.08 56.00 Protoxide of iron, with traces of manganese and chromium{ 12.43 }11.13 Alumina 1.42 Lime 9.00 9.94 Magnesia 21.35 21.96 Soda traces traces Water of constitution .97 .97 96.25 100.00 Diallage, (Ċa, Mg, Fe) Si.—The first mention of this mineral in New Zealand is by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 438) as occurring in diorites on the West Coast, and during his trip round the West Coast Sounds in 1863, he collected specimens in gabbro from Hokuri Creek, Martin's Bay, Lake McKerrow, and the head of Kakapo Lake; he again mentions it (Trans. N.Z. Inst., vol. ii., p. 377) as dykes in the Dun Mountain. It is mentioned by Dr. v. Haast as occurring in gabbro in the Mt. Torlesse Range and Upper Rakaia (Jurors' Rep. N.Z. Ex., 1865, p. 257); by Mr. J. C. Crawford in reefs traversing mesozoic limestones at Waikekino (Trans. N.Z. Inst., vol. ii., p. 351); by Mr. E. H. Davis, at the Dun Mountain (Geol. Rep., 1870–71, p. 112); and again by Prof. Liversidge in his description of the minerals in the Otago Museum (Trans. N.Z. Inst., vol. x., p. 496), from Lake McKerrow and Dun Mountain. There is a specimen in the collection of the Colonial Museum, from Kakapo Lake, of a dark-green colour and metallic lustre, which is not well marked, corresponding with the specimen described by Prof. Liversidge from Lake McKerrow. Hypersthene, (Mg, Fe) Si.—This mineral is mentioned by Dr. Hector in diorite rocks on the West Coast (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 438), and was collected by him from Warp Point, Kaduku River, in 1863. It is again mentioned by Dr. v. Haast in hypersthenite, Malvern Hills (Jurors' Rep. N.Z. Ex., 1865, p. 257); by Mr. E. H. Davis at the Dun Mountain (Geol. Rep., 1870–71, p. 112); and by Prof. Liversidge as occurring in the collection of the Otago Museum from Warp Point, Kaduku River (Trans. N.Z. Inst., vol. x., p. 497).

It has been collected from Red Hill, Collingwood, by Dr. Hector (Col. Mus. & Lab. Rep., xiii., p. 35). Bronzite, Mg (Fe) Si.—The occurrence of this mineral in diorite rocks of the West Coast is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 438), and by Mr. E. H. Davis at the Dun Mountain (Geol. Rep. 1870–71, p. 112). A specimen from the Dun Mountain in the colletion of the Colonial Museum consists of crystals of a brownish-green colour imbedded in a network of veins of picrosmine. Hydrous Silicates of Magnesia and Lime. Meerschaum, 2 Mg2 Si3 + 3 H.—The occurrence of this mineral at the Dun Mountain is mentioned (Col. Mus. & Lab. Rep., vi., p. 16), the specimen having been collected by the late Mr. E. H. Davis. “Its colour was pure white, lustre feeble, opaque, structure amorphous; to the touch it has that soft smoothness peculiar to minerals of this class; hardness 2 to 3; easily decomposed by hydrochloric acid. It occurs in contact with massive white quartz, enclosing columnar detached crystals of a dark green colour, probably hypersthene.” Its composition is— Silica 53.76 Lime 2.36 Alumina 4.35 Iron oxides traces Magnesia 20.36 Water of constitution 19.17 100.00 Dermatin, (Mg, Fe) Si + 2 H.—This mineral is mentioned by Mr. E. H. Davis (Geol. Rep., 1870–71, p. 112) as occurring in thin faces with smooth polished surfaces at the Dun Mountain. Talc, Mg3 Si4 + H.—The occurrence of this mineral is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 438) in quartz from the West Coast Sounds; and again by Mr. D. Macfarlane (Geol. Rep., 1876–77, p. 27) at Jackson's Bay. There are specimens in the collection of the Colonial Museum from Collingwood and Jackson's Bay, both being of a pale green colour. It is somewhat widely distributed on the West Coast of the South Island, being frequently found associated with the crystalline rocks of that district. Steatite is mentioned by Dr. Hector at Milford Sound (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437), and it occurs in considerable quantities at Collingwood in a massive form and of a grey pink and green colour; some specimens are foliated. Its position is shown on the geological map of Collingwood published by Dr. Hector (Geol. Rep., 1873–74, p. iv.)

Serpentine, Mg3 Si2 + 2 H.—This mineral is somewhat widely distributed in New Zealand, occupying as a rule the junction line or thereabouts between the Lower Carboniferous and Upper Devonian rocks, but it is also found associated with nephrite at Milford Sound. Dr. Hector says (Jurors' Rep. N.Z. Ex., 1865, p. 412):—“This mineral occurs in New Zealand in two forms—Common Serpentine, that forms extensive rock-masses characteristic of the mineral ground in various parts of the South Island in the provinces of both Nelson and Otago; and Noble Serpentine, which occurs in thin veins associated with the jado or greenstone of the Maoris, by whom it is distinguished by the name of Tangiwai.” The principal development of the common serpentine is in Nelson, where what is known as the mineral belt may be traced down D'Urville Island through the Dun Mountain to Aniseed Valley, an isolated patch occurring again at Red Hill. It is alluded to by several observers, such as Dr. v. Hochstetter, Dr. Hector, Mr. E. H. Davis, Mr. A. McKay, and myself, in reports made from time to time on various parts of the district, and is described by Mr. E. H. Davis (Geol. Rep., 1870–71, p. 111) thus:—“Dun Mountain serpentine as a rule is of a poor variety, generally a dark green, almost black colour, appearing lighter by transmitted light: translucent at the edges and rather brittle.” It is mentioned by Mr. J. C. Crawford as occurring in small quantities in the palæozoic rocks of Wellington (Trans. N.Z. Inst., vol. i., p. 4), and again at Ruamahunga (Trans. N.Z. Inst. vol. ii., p. 345); by Dr. v. Haast as veins in the Mt. Cook range and some other localities in the Southern Alps (Jurors' Rep. N.Z. Ex., 1865, p. 257); by Mr. J. Buchanan in the Awatere River, Marlborough (Geol. Rep., 1866–67, p. 35) and by Mr. D. Macfarlane at Jackson's Bay (Geol. Rep., 1876–77, p. 27). Specimens have also been forwarded to the Colonial Museum from Island Bay, Wellington, by Mr. W. F. Barraud; from Southland (Windly Creek) by Captain Hutton; from Auckland by Mr. J. B. Gillies; from Pelorus Sound by Mr. Duncan; and from the Dart River by the Hon. Captain Fraser. Noble serpentine, as before mentioned, occurs at Milford Sound, and is described by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 412) as follows:—“It occurs as boulders of various sizes, and generally much water-worn. Some of the smaller pieces when cut and polished are very attractive on account of their beautiful deep sea-green colour, their translucency, their purity, and remarkable closeness of grain. This mineral is somewhat soft, and, breaking readily, is capable of being worked into any shape with the greatest ease, and for ornamental work generally is well adapted. Its general characters are as follow: Colour, dull green and mottled black lustre, slightly resinous; fracture, splintery; streak, dirty white; hardness

4.6; sp. gr. 2.592. Is completely decomposed by hydrochloric acid. In blowpipe flame infusible, turns faint buff colour, no distinct soda reaction, but slight reaction of manganese with the proper fluxes.” Analysis. 1. 2. 3. Silica 40.20 41.20 45.91 Protoxide of iron 12.10 12.10 1.67 Alumina traces traces 5.63 Manganese " " traces Chromium " " " Magnesia 33.20 34.02 35.07 Water of constitution 12.70 12.74 12.67 98.20 100.06 100.95 This is alluded to by Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 497) as marmolite. There is also a specimen in the collection of the Colonial Museum, from Jackson's Bay, which is of a grass-green colour, translucent and laminated. Antigorite.—The occurrence of this mineral at the Dun Mountain is mentioned by the late Mr. E. H. Davis (Geol. Rep., 1870–71, p. 112). Hectorite occurs at the Dun Mountain, Nelson (for description see below, Art. xlviii.). Picrolite, a coarsely fibrous variety, of dark dirty green colour, occurs at the Dun Mountain. Chrysotile occurs as thin veins of a silky texture and pale green colour traversing the dark green serpentine of the Dun Mountain. Picrosmine, 2 Mg Si + H.—A massive sectile variety of this mineral, of a greenish-grey colour, occurs associated with chromite at the Dun Mountain; it is also found as a network of veins, in which crystals of bronzite occur, in the same district. Schiller Spar, Mg (Fe, Ċa), Si (Al Ar Fe) + H.—The occurrence of this mineral with pyrites on the West Coast is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 266). Chlorite, 2 R Si + R2 Al + 3 H, occurs as a constituent of the chlorite schists, which are found in many localities between Otago and Nelson on the West Coast side of the South Island. It is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) in the schist of the West Coast, and also as an amorphous form in the vesicular basalts of Otago Heads and elsewhere; by Dr. v. Haast in laminæ in the metamorphic schists of the West Coast, (Jurors' Rep. N.Z. Ex., 1865, p. 257); by Mr. Skey, at Tararu Creek, Thames (Geol. Rep., 1870–71, p. 88); by myself in chlorite schists at the Fox Glacier, Westland (Geol. Rep., 1874–76, p. 73); and by Professor Liversidge, from Deep Creek, Kakapo Lake (Trans. N.Z. Inst., vol. x., p. 497).

Heulandite, Äl Si3 + Ċa Si3 + 5 H.—The occurrence of this mineral in amygdaloidal traps associated with felsite porphyries in Canterbury, is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257). Apophyllite, 8 (Ċa Sia + 2 H) + K F, is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 267) occurring in amygdaloids at Rangitata, and ichthyophthalmite in felsite porphyries at Turnagain Point, Rangitata. Stilbite, Äl Si3 + Ċa Si3 + 6 H, is mentioned as occurring at Turnagain Point, Rangitata, by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257). It also occurs at Tokatoka on the Wairoa River, Auckland, as radiating pearly crystals in a trachytic rock which forms Mts. Maungarahu and Tokatoka, and it is again found in a similar rock which occurs at Pukekorero, a mountain lying between the Kaiwaka arm of Kaipara Harbour and Mangawhai. Prof. Liversidge (Trans. N.Z. Inst., vol. x., p. 500) also alludes to its occurrence at Dunedin in amygdaloidal basalts as follows:—“In the cavities of these specimens are minute detached crystals of one of the zeolites. The form appears to be that of a rhombic prism capped with the pyramid; this is a combination often assumed by stilbite, and in addition the little crystals possess a very high lustre, not unlike that of stilbite; moreover, they behave like that mineral before the blowpipe, hence they probably belong to the same species. Prehnite, Äl Si + 2 Ċa Si + H.—This mineral is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266 and 437) as occurring in the trap rocks of Moeraki and Otepopo, and R. Daintree, Esq., F.G.S. (Trans. N.Z. Inst., vol. vii., p. 458), in speaking of a granite rock from the Snowy Peak Range, Canterbury, says:—“There is a yellowish mineral with a fibrous radial structure seen both in the specimen and the section. It is evidently a secondary formation, filling spaces between the constituents. It is probably prehnite. Natrolite, Äl Si2 + Na Si + 2 H.—The occurrence of this mineral in vesicular basalts near Dunedin is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 267 and 438), and in the volcanic rocks of Banks Peninsula, by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257). It is also mentioned in the old catalogues of the Otago Museum as specimens from Oamaru in trachyte, from Mount Livingstone and from Look-out Point. There are numerous specimens of this mineral in the collection of the Colonial Museum, in cavities in the basalts from Dunedin. They are arranged in beautiful little tufts of fine acicular crystals, sometimes alone, and sometimes on chabasite; in other specimens they are massive but mammillated, and in others they are composed of short rhombic prisms with pyramidal ends, but these also occur in tuft-like groups. There is also a

specimen from Whakahara, on the Wairoa River, Auckland, where it occurs in a vein running through certain tufaceous beds in the Whakahara Saddle, between Maungarahu and Tokatoka. The crystals are long slender rhombic prisms, ∞P with pyramidal ends P. Chabasite, Äl Si3 + Ċa (Na, K) Si + 6 H, is mentioned by Dr. Hector in vesicular basalts near Dunedin (Jurors' Rep. N.Z. Ex., 1865, p. 267), and by Dr. v. Haast in the trachyte of Banks Peninsula (Jurors' Rep. N.Z. Ex., 1865, p. 257; there is also in the Catalogue of the Otago Museum a mention of a specimen from Helenburn. The specimens in the collection of the Colonial Museum are all from the first-named locality, and they consist of small rhombohedral crystals in cavities in the basaltic rocks. B.B. it deflagrates slightly and fuses to a porous enamel; colour brownish-white, no soda reaction visible. Gmelinite, Äl Si3 + Na (Ċa, K) Si + 6 H, is mentioned by Dr. Hector in vesicular basalts near Dunedin (Jurors' Rep. N.Z. Ex., 1865, p. 267). Specimens from this locality in the collection of the Colonial Museum are pure white, small hexagonal pyramids with OP ends. B.B. gives faint soda reaction only. Silicates of Alumina, Hydrous and Anhydrous. Kaolin, Äl Si2 + 2 H, is mentioned by Dr. Hector at the Manuherikia Plains and Arrow River (Jurors' Rep. N.Z. Ex., 1865, pp. 267, 438), and at the Whau, Auckland (Jurors' Rep. N.Z. Ex., 1865, p. 35); and I have mentioned its occurrence at Mt. Somers, Canterbury (Geol. Rep., 1876–77, p. 6), where it is formed by the decomposition of felsite porphyries. Specimens from drift at Collingwood have also been forwarded to the Museum. Clay.—All the varieties of clay are found in the colony, but, for a detailed description of these with their analyses, I must refer the reader to the “Manual of the Mineral Resources of New Zealand,” by Dr. Hector, in course of publication. A very fine sample of pipeclay occurs at Hakateramea, Canterbury. Bole occurs as nests in the doleritic rocks passed through in the Lyttelton tunnel, and is associated with crystals of magnetite. Its specific gravity is 2.089, and composition as follows:— Silica 44.78 Alumina 15.66 Iron 16.87 Manganese .60 Lime 2.02 Magnesia 5.02 Potash 2.69 Water of constitution 12.36 100.00

Halloysite, Äl Si + 4 H.—The occurrence of this mineral in decomposing basalts around Dunedin is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 438), and a specimen from the Water of Leith is described by Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 499) as follows:—“An opaque white earthy substance, soft and soapy; associated with it is a little black halloysite; when immersed in water it gives off airbubbles rapidly, accompanied by a singing sound; falls to pieces and becomes translucent on the thin edges; breaks with a conchoidal fracture; adheres strongly to the tongue; yields to the thumb-nail, and affords a shining streak; possesses an earthy smell.” A sample of an impure form from Scinde Island, Napier, where it occurs in considerable quantities (Col. Mus. and Lab. Rep., vii., p. 18), was forwarded to the Museum in 1872, and had the following composition:— Silica 58.22 Sesquioxide of iron 5.82 Alumina 24.34 Lime 2.02 Magnesia 2.58 Water 4.81 Alkalies and loss 2.20 100.00 the high proportion of silica being due to the presence of grains of free quartz, which constitute the principal impurity. A specimen from the Bay of Islands was forwarded by Mr. J. Williamson in 1874, and is of a yellowish-brown colour, and very fine grain; three specimens from the Drury and Hunua Ranges were forwarded by the Hon. H. Chamberlin in 1875, and a specimen collected from Whangaroa Harbour, by Mr. A. McKay, during the same year. Fuller's Earth.—Specimens from Great Barrier Island and the Hot Springs, were exhibited at the Dunedin Exhibition of 1865, by the Auckland local committee, and are mentioned (Jurors' Rep. N.Z. Ex., 1865, p. 253). Palagonite, (Äl Fe) Si3 + 3 (Ċa, Mg, Na) Si + 10 H.—The occurrence of this mineral as angular fragments in palagonite tufas is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257), at Harper Hills, near the Selwyn, and at Two Brothers, Ashburton, as also another variety changing insensibly into a pitch opal, enclosing leaves and stalks silicified, in the same localities. A specimen from Taipo Hill, Otago, was forwarded in 1868 by Mr. C. Teschmaker, where it occurs as a large seam 60 feet thick, running in the direction of a limestone quarry. Its characters, as described by Mr. Skey, are—massive; colour, black; hardness, 4.5; somewhat, friable; is

intersected by numerous small white veins. Readily decomposed by H. Cl. at a temperature of 212° Fah.; lost 13 per cent. water,-but as it is very probable this is in greater part or altogether constitutional along with that requiring a higher temperature for its expulsion, the whole of the water present in the stone is entered in the appended analysis under one head:— Silica 88.82 Alumina 23.17 Oxides of iron 6.30 Lime 3.65 Magnesia 3.27 Alkalies 2.08 Water 22.76 Carbonaceous matter traces 100.00 Schrötterite, Äl2 Si + 8 H.—Professor Liversidge (Trans. N.Z. Inst., vol. x., p. 500) mentions a mineral from the Malvern Hills, Canterbury, which is probably schrötterite. His description is as follows:—“In rounded wax-like masses, filling the cavities of an amygdaloidal trachyte (?) rock, and has a mammillated incrustation upon its surface; green, grey, and white; hardness about 3.5; streak, white; rather tough; breaks into more or less conchoidal flakes; translucent; waxy lustre. Before the blowpipe it becomes white and opaque and much harder, intumesces slightly and tinges the flame green; affords deep blue when ignited with cobalt nitrate; does not gelatinize with hydrochloric acid, but granular silica is thrown down; gives off much water when heated in a closed tube.' Pimelite, 2 Äl Si + 3 Mg Si + 10 H.—The occurrence of this mineral filling cavities in amygdaloidal rocks, at Malvern Hills, Clent Hills, etc., is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257). Idocrase (Vesuvianite), 3 (Ċa, Mg)3 Si + 2 Äl Si2.—This mineral occurs as dirty green, fluted, prismatic crystals, in quartz associated with the crystalline rocks of Dusky Sound; specimens having been forwarded by Mr. W. Docherty. The larger crystals have a resinous lustre and the smaller ones, which are of a brighter green, are more pellucid. Epidote, 2 (Äl,Fe) Si3 + 3 Ċa Si.—The occurrence of this mineral in gneiss granite and granulite of the West Coast is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 266) and by Dr. v. Haast in the diorites of Mt. Torlesse range (Jurors' Rep. N.Z. Ex., 1865, p. 257) and in the melaphyres of the Mt. Somers district (Geol. Rep., 1873–74, p. 9). A massive form from Wairarapa, Wellington, of a greenish-grey colour, is also in the collection of the Colonial Museum. Before the blowpipe it

fuses easily, and with intumescence to a colourless transparent bead. Easily decomposed by hydrochloric acid, with separation of gelatinous silica. Analysis. Silica 44.71 Iron 14.66 Alumina 11.47 Lime 22.93 Magnesia 2.13 Water of constitution 4.10 100.00 Kyanite (Disthene), Äl Si.—This mineral is mentioned in the Catalogue of the Colonial Museum (p. 119) from Westland. The specimen is of a beautiful cobalt blue colour, and associated with quartz. The crystals are not very distinct. Chiastolite.—Crystals of this mineral, of a dirty-grey colour, imbedded in clay slate, from Slate River, Collingwood, are in the collection of the Colonial Museum. Leucite, Äl2 Si3 + K Si.—The occurrence of this mineral in leucitic basalt is mentioned (Col. Mus. and Lab. Rep., x., p. 48) from Castle Point, Napier, having been collected by Mr. A. McKay. Scapolite, Äl2 Si3 + (Ċa, Na) Si.—The occurrence of this mineral in a massive form at the Dun Mountain is mentioned by Mr. E. H. Davis (Geol. Rep., 1870–71, p. 112), and an impure form of the same mineral was forwarded from the Maitai Valley, by the Nelson Museum, in 1868. The specimens collected by Mr. E. H. Davis were analyzed at the Colonial Laboratory, with the following results;— (1.) (2.) (3.) Silica 48.63 48.29 43.06 Lime 25.39 26.59 24.34 Alumina 20.70 20.47 11.47 Iron sesquioxides, with manganese traces traces 7.24 Magnesia 2.93 .85 9.06 Water 2.35 2.53 3.42 Loss 1.27 1.41 100.00 100.00 100.00 Nos. 1 and 2 are white minerals, with rare mottlings and striæ of a dark red colour; they are dull and opaque, but in thin sections translucent; easily fusible in the blowpipe, with intumescence to transparent beads, giving faint reaction of soda. No. 3 has a general similarity to the others, but is uncoloured, and fuses to a yellow-coloured bead in the blowpipe

flame (Col. Mus. and Lab. Rep., vi., p. 16). Specimens have also been brought from the Buller River by Dr. Hector (Col. Mus. and Lab. Rep., vii., p. 26), and from the Wairau River, Nelson, by Mr. A. McKay (Col. Mus. and Lab. Rep., xiii., p. 35). Garnets, R3 Si2 + R Si, are of very common occurrence in New Zealand, associated with the crystalline rocks of the West Coast, and also with the quartz porphyries and pitchstones of Canterbury; they are also frequently found in the auriferous washes of various localities, numerous specimens having been forwarded by diggers who have mistaken them for tinstone. They are mentioned by Dr. v. Hochstetter in mica schist at Collingwood, and in the gold-wash of the Takaka Valley (New Zealand, 1863, Eng. ed., pp. 103, 107); by Dr. Hector, (manganese variety), in gneiss granite and quartzite of the West Coast (Jurors' Rep. N.Z. Ex., 1865 pp. 266, 437), in the Kakanui River, as lime-iron garnets (Jurors' Rep. N.Z. Ex., 1865, p. 437), in the gold-wash of Stewart Island (Trans. N.Z. Inst., vol. ii., p. 185), and in the gold-wash of the South (Trans. N.Z. Inst., vol. ii., p. 371); by Dr. v. Haast, as almandine in the quartz porphyries and pitchstones of the Malvern Hills and Mt. Somers (Jurors' Rep. N.Z. Ex., 1865, p. 257, and Geol. Rep., 1873–74, p. 9); by R. Daintree, Esq., F.G.S., in trachytic rocks and pitchstones of Snowy Peak Range (Trans., N.Z. Inst., vol. vii., p. 459, and by myself in gneiss and quartzose porphyry (granulite) at Resolution Island. Besides these garnets have been forwarded from Nelson by Mr. C. Broad, from Karaka Creek, Thames, by Mr. Davis, from Brighton, Wanganui, by Mr. Duigan, from Anatoki, by Dr. Hector, and from Mount Rangitoto, Westland, by Mr. E. Steward. There are, in the collection of the Colonial Museum, specimens of almandine, of a pinkish red colour, in granulite, from Dusky Sound; of fine garnet sand, from the West Coast of Nelson, and of iron garnets in schist from Collingwood, in gneiss from Dusky Sound, and also in a quartz vein from the same locality, and as a garnet-rock from Otago. The prevailing crystalline form is the rhombic dodecahedron, but the icositetrahedron is also of frequent occurrence in the specimens from Dusky Sound. Muscovite, 3 Äl Si + K Si3, is of very frequent occurrence in New Zealand as a constituent of the mica schist, gneiss, and granite of the West Coast. Some fine plates occur at Charleston, and also in Mitre Peak, Milford Sound. Its occurrence is mentioned by Dr. Hector in the schists and gneiss of the West Coast (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437), and in a dyke granite on Great Barrier Island (Trans. N.Z. Inst., vol. ii., p. 375); in the granites and schists of the West Coast, by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257; and as brown mica in a trachytic rock and silvery mica in a granitic rock at Snowy Peak Range, by R.

Daintree, Esq., F.G.S. (Trans. N.Z. Inst., vol. vii., p. 458), and is again alluded to by Prof. Liversidge, from Dusky Bay and Charleston. (Trans. N.Z. Inst., vol. x., p. 497). Lepidolite.—The occurrence of this mineral is mentioned by Dr. Hector in the gneiss of the West Coast and in the marble of Thompson Sound (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437). Biotite, Äl Si + (Mg, K, Fe)3 Si, is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) as occurring on the West Coast, and there are specimens in the collection of the Colonial Museum from Milford Sound and Doubtful Inlet. In the last locality it occurs as a black-green mica rock with numerous minute crystals of zircon. Rubellane is mentioned by Dr. v. Haast as occurring in the volcanic rocks of Banks Peninsula (Jurors' Rep. N.Z. Ex., 1865, p. 257). Lepidomelane, (Al Fe) Si + (Fe, K) Si.—This mineral is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) in the schists and gneiss of the West Coast, and there are specimens in the collection of the Colonial Museum from Milford Sound, where it occurs in thin hexagonal plates of a blackish-green colour, bronze by reflected light in certain positions; streak, dirty green. Thin laminæ slightly flexible, rather brittle. Before the blowpipe becomes bronze-yellow, and does not fuse. Margarite, Äl2 Si + (Ċa, Na, Mg) Si + H, is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437) in the schists and gneiss of the West Coast, and by Dr. v. Haast from the same localities (Jurors' Rep. N.Z. Ex., 1865, p. 257). There is a small specimen in the collection of the Colonial Museum from Milford Sound of a pearl-grey colour. Chrome Mica.—This mineral is a chrome-magnesian mica, occurring in flat tabular plates of a green colour, and belongs to the hexagonal system. It is talcose in appearance and feels soapy to the touch, but Mr. Skey's analysis precludes its falling into the talc group, and it must therefore be considered as a chrome-magnesian mica, the percentage of water in which is somewhat high. A somewhat similar mineral from Schwartzenstein, analyzed by Schafhautl, is mentioned in Dana's System of Mineralogy, but it contains more silica and less alumina than this specimen. Schwartzenstein. Dead-horse Gully. Silica 47.68 39.25 Alumina 15.15 22.12 Chromic oxide 5.90 1.56 Ferric oxide 5.72 18.69 Manganous oxide 1.05 .41 Magnesic oxide 11.58 10.60 Sodic oxide 1.17 1.13 Potassic oxide 7.27 1.13 Water 2.86 4.06 Lime — 2.18 98.38 100.00

It was obtained from Dead-horse Gully, Lake Wakatipu, by Mr. McKay, who states that it occurs on the strike of the Moke Creek copper lode. A similar mineral has been forwarded by Mr. W. Docherty from Dusky Sound where it occurs in gneiss. Orthoclase, Äl Si3 + K Si3, occurs as a constituent of the granites, syenites, gneiss, trachytes and Hyolites of New Zealand. It is mentioned by Dr. Hector as occurring in all the schists and crystalline rocks of the West Coast (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437), in granite from the Auckland Islands, and in granite and hornblende rocks from Ruapuke (Trans. N.Z. Inst., vol. ii., pp. 183, 185), in dyke granite at Great Barrier Island (Trans. N.Z. Inst., vol. ii, p. 375), and as sanidine in the trachyte of the Sugar Loaves, Taranaki (Geol. Rep., 1866–67, p. 8); by Dr. v. Hochstetter as sanidine in the rhyolitic tufas of Lake Taupo, and flesh-coloured felspar in the syenite of the Boulder Bank, Nelson (New Zealand, Eng. ed., pp. 385, 471); by Dr. v. Haast in the granite and other crystalline rocks of the West Coast, and as sanidine in the trachytes and trachydolerites of Banks Peninsula (Jurors' Rep. N.Z. Ex., 1865, p. 257, and Trans. N.Z. Inst., vol. xi., p. 504); and by R. Daintree, Esq., F.G.S., in dolerite of the Hororata district and Acheron section; in trachytic rocks at Mt. Misery and Snowy Peak Range and also in a granitic rock and pitchstone at Snowy Peak Range (Trans. N.Z. Inst., vol. vii., p. 458). The specimens in the collection of the Colonial Museum are a pink variety in granite from Dusky Sound, and a yellowish white specimen in a granitic dyke from Great Barrier Island. Albite, Äl Si3 + Na Si3, is mentioned by Dr. Hector in the diorites of the West Coast (Jurors' Rep. N.Z. Ex., 1865, pp. 266, 437); by Dr. v. Haast in dioritic porphyries of the River Wilkes and Makarora Ranges (Jurors' Rep. N.Z. Ex., 1865, p. 257); by Mr. E. H. Davis at the Dun Mountain (Geol. Rep., 1870–71, p. 112); and by Prof. Liversidge from George Sound (Trans. N.Z. Inst., vol. x., p. 498). There is a white massive form, with chlorite, from Maori Point, Shotover, in the collection of the Colonial Museum. Labradorite, Äl Si2 + (Ċa, Na) Si, is mentioned by Dr. Hector in trachydolerites from Flagstaff Hill (Jurors' Rep. N.Z. Ex., 1865, p. 437) and by Dr. v. Haast in lava streams at Banks Peninsula (Jurors' Rep. N.Z. Ex., 1865, p. 257), and in the basalts and as large crystals in the dolerites of Banks Peninsula (Trans. N.Z. Inst., vol. xi., p. 499). There is a specimen in the collection of the Colonial Museum from Purahanui, Otago, of a dirty brown colour, showing play of colours on cleavage planes, and another, of a grey colour, in dolerite from Mt. Charles, Otago. Saussurite is mentioned by Dr. v. Haast in gabbro from Mt. Torlesse Jurors' Rep. N.Z. Ex., 1865, p. 257).

Oligoclase, 2 Äl Si3 + (Na, Ċa)2 Si3, is mentioned by Dr. v. Haast in quartz porphyries of Mt. Misery and Malvern Hills (Jurors' Rep. N.Z. Ex., 1865, p. 257), and R. Daintree, Esq., F.G.S. (Trans. N.Z. Inst., vol. vii., p. 458), mentions the occurrence of a plagioclase felspar, which is probably oligoclase, in granite from Snowy Peak Range. Obsidian is mentioned, by Dr., v. Hochstetter, with rhyolites in the Taupo district (New Zealand, Eng. ed., p. 407); by Dr. v. Haast, on the sides of trachytic dykes (selbands) in Banks Peninsula (Jurors' Rep. N.Z. Ex., 1865, p. 257, and Trans. N.Z. Inst., vol. xi., p. 504); and by Mr. J. A. Pond, in the volcanic rock from Mr. Firth's well near Mt. Eden, Auckland (Trans. N.Z. Inst., vol. vii., p. 406). Its distribution in the North Island is widespead in the volcanic regions which occupy the central and north-east portions of the island; but, so far as I am aware, no solid flöes have been discovered, and the mineral has only been found in isolated blocks. It was formerly largely employed by the Maoris for the manufacture of weapons and implements. There are several specimens in the collection of the Colonial Museum from Taupo and White Island. Pumice.—Is found throughout the volcanic region of the central portion of the North Island whence it is brought down to the sea by rivers, and distributed along the coast by the action of the tides and currents. It is mentioned by Dr. v. Hochstetter (New Zealand, Eng. ed., p. 43) as occurring in plateaux round Lake Taupo, 2,000 feet above the sea and he states (p. 384) that Mr. Grace's house is built of it. It is mentioned (Jurors' Rep. N.Z. Ex., 1865, pp. 35, 253) from the beach near Napier, where it is found in considerable quantities, brought down by the rivers from the north and also from Waikato, and Mr. J. C. Crawford (Trans. N.Z. Inst., vol. vi., p. 356) states that it occurs in large quantities at Tokano and (Trans. N.Z. Inst., vol. viii., p. 377) that pumice floats down the Wanganui River in such quantities that it would be easy for a ship, anchored in the river, to put out nets and so load the ship. Around the volcanic group of Ruapehu and Tongariro there are immense areas covered with pumice, and at Kereru, Napier, and many other localities on the east coast of the North Island, there are extensive deposits of compact white pumice-sand, which are mentioned by Mr. McKay (Geol. Rep., 1876–77, p. 81). Pitchstone.—The only district in New Zealand where this mineral occurs is between Mt. Somers and Snowy Peak, where it is associated with quartz porphyries of which it appears to be the vitreous form, a complete series representing the change from a fluid pitchstone, through various stages, to a quartz porphyry with felsitic base and small crystals of quartz and garnet in which no fluxion structure is visible. It is of all colours, from grey to

brown and red, and occurs in considerable quantities at some places. It is mentioned by Dr. v. Haast (Jurors' Rep. N.Z. Ex., 1865, p. 257, and Geol. Rep., 1873–74, p. 9) associated with the quartz porphyries of Mount Somers and Snowy Peak. Aluminates of Magnesia and Glucina. Spinel, Mg Äl.—The occurrence of rubies with garnet and topaz in the alluvium of Waipori, Otago, is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, p. 416). This mineral is also mentioned from Manawatu, Wellington (Col. Mus. and Lab. Rep., v., p. 18) as rhombic dodecahedrons, and nearly opaque. They were not analyzed, and so are very probably garnets. Silicates of Glucina, Zirconia, Thoria, and Yttria. Zircon, Żr, Si.—The occurrence of this mineral is mentioned by Dr. Hector (Jurors' Rep. N.Z. Ex., 1865, pp. 417, 438), who says “crystals of zircon were exhibited, in the Museum of the Geological Survey, from Timbril's Gully,” and (Trans. N.Z. Inst., vol. ii., p. 371) with platinum and gold in the wash of the south; and by Dr. v. Haast from the western slopes of the Southern Alps (Geol. Rep., 1870–71, p. 24). In the collection of the Colonial Museum there is a specimen of a biotite rock from Doubtful Inlet, Otago, in which there are numerous minute tetragonal prisms with pyramidal ends of a bright red colour, transparent, which are probably zircons. Topaz, 5 Äl Si + (Al F3 + Si F2).—Is mentioned by Dr. Hector at Chatto Creek, Arrow River, and Waipori (Jurors' Rep. N.Z. Ex., 1865, pp. 265, 438); and (p. 416) he says, “in collections from the Otago Goldfields' department were some uncut topazes as large as pigeons' eggs, and of a pure white colour. Several smaller topazes of various colours have lately come into the possession of the Geological Survey of Otago from the neighbourhood of Waipori, where they are found in the alluvium along with rubies, garnets,” etc. Emerald, Äl Si3 + 3 Ġl Si.—Specimens of this mineral have been forwarded from Dusky Sound by Mr. W. Docherty, of which Mr. Skey says:—“This is a somewhat rare mineral collected by Mr. William Docherty, from a vein in the vicinity of Dusky Sound. When tested, it was found to be the mineral beryl, the distinguishing feature of which is the presence therein of the rare metal glucinum (beryllum.) Usually, this is to the extent of 12 to 15 per cent. in specimens of this kind. The mineral is of a full rich green colour, which it owes to the presence of sesquioxide of chrome. It occurs at Dusky Bay, in a pyrrhotiniferous quartz, forming little nests of confusedly crystalline masses having a tendency to assume a tabular form.”

I have since examined these specimens, and find the following sections of crystals, which confirm Mr. Skey's determination:— The hardness of the mineral is about 7, and it occurs in the more quartzoze portions of a syenitic gneiss, associated with garnets, pyrrhotine and chrome mica, as other accessory minerals. Tourmaline, n R Si + R3 Si, is mentioned by Dr. Hector in the granite and gneiss of the West Coast (Jurors' Rep. N.Z. Ex., 1865, p. 266); by Dr. v. Haast, in granite, at Mosquito Hill on the West Coast (Jurors' Rep. N.Z. Ex., 1865, p. 257), and by myself in micaceous and hornblende schists at Resolution Island (Geol. Rep., 1874–76, p. 31). There are some very fine specimens of schorl in chlorite schist, from Collingwood, in the collection of the Colonial Museum, arranged as long, black, striated prisms in broken strings which radiate from a centre; they vary from a sixteenth of an inch to a quarter of an inch in diameter. Some very beautiful little acicular crystals in quartz, from Bedstead Gully, Collingwood, are also in the collection; they are of a deep black colour, and red by transmitted light. A blackish green variety also occurs in the granite of Tata Island, Nelson.

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Bibliographic details

Transactions and Proceedings of the Royal Society of New Zealand, Volume 15, 1882, Unnumbered Page

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Art. XLVII.—Notes on the Mineralogy of New Zealand. Transactions and Proceedings of the Royal Society of New Zealand, Volume 15, 1882, Unnumbered Page

Art. XLVII.—Notes on the Mineralogy of New Zealand. Transactions and Proceedings of the Royal Society of New Zealand, Volume 15, 1882, Unnumbered Page