NEW ZEALAND MINERAL COURT AT THE EXHIBITION.

Otago Witness, Issue 1891, 1 May 1890, Page 11

NEW ZEALAND MINERAL COURT AT THE EXHIBITION.

x. Apart from gold, which ha 3in the past, and still does enter largely into the resources of the colony, the other mineral products aie unimportant. This does not result from their scarcity so much as from the fact that systematic search has not been made for them, and in the case of those minerals having a commercial value and known to exist in quantity no adequate attempt has been made to utilise them. All of the most important minerals have been found in the colony, but as yet no lorge mining concerns other than gold mines have been attempted. Nearly every variety of iron ore has been found in the colony, but the only attempts to work these have been in connection with the black sand which occurs bo plentifully on some parts of the coast, especially at Taranaki and Onehunga in the North Island. The iron exhibits of the Onehunga Company, showing the raw material and the finished product in great variety, prove that these sands are eminently suited for iron manufacture Brown hematite ore is found at Parapara, Nelson, where immense quantities occur at the surface of the ground Another deposit of the same ore occurs on the west side of Mount Peel, where the deposit is 60ft thick, and contains about 56 per cent, of the metal. The lode has been traced for a distance of about three miles, and beyond that it is said to swell out to a deposit a mile wide. Specular iron ore occurs in the Dun Mountains, Nelson, in irregular veins in greenstone rocks. The ore contains 63 per cent, of the metal. The same ore has been found at Shotover, Otago, where a 6ft vein occurs in mica-chist rock. The extent of this lode is not known. Compact iron ore occurs in a vein, the thickness of which is not known, in D'Urville Island, Nelson. The formation is diorite, slate, with serpentine and chrome. The ore assays 63 per cent, of iron. Magnetic iron is found in the massive form, in addition to the black sand deposits, in several parts of the colony —at the Dun Mountains, Nelson, where a vein 16in thick occurs in serpentinous slate; at Wakatipu, Otago, in a vein in mica schist; at the Thames, Auckland, in a vein in ferriferous slate; and in iron band ore, formed by layers of black sand having become cemented together with hematite. Massive magnetite is also said to be known to exist in ttat part of Otago forming the watershed between the Clutha and Waiwera rivers, where the high range is composed largely of this ore of iron. It is tte ore that has made Sweden so famous for its iron, and when the iron industry comes to take root in Otago the honours will be divided. Spathic iron ore occurs in quantity in the Collingwcod district, Nelson. In the form of black-band ore this ore alternates with the coal seams at Collingwood. These ores contain over 40 per cent, of iron. Altogether the iron deposits of the colony are very important, and must, in the not distant future, form a considerable item in the mineral resources of New Zealand.

Chrome ore has been found in different parts of the colony. This ore generally occurs as a mixture of chrome-iron and alumina, and is generally associated with magnesian rock. Veins 12ft thick have been found containing as high as 80 per cent, of chrome ore. This ore has been exported in some quantity from Nelson. The exports up to the end of 1886 amounted to 5306 tons, valued at £37,367. Good ore is worth from £11 to £20 per ton.

Copper ore has been mined for some time at the Great Barrier Island 'aud Kawau Island, Auckland, and to a small extent at Doubtless Bay. The sulphide ore has been found associated with metamorphic rocks at Waitahuna, Otago, where a 4ft pyrites lode exists. Cuprite and copper glance has been found in the Dun Mountains, Nelson. At D'Urville Island the ore has been traced to a depth of 100 ft, some of the better samples yielding 45 per cent, of metal. A lode of copper pyrites has been found at Dusky Pound, Otago. A lode from 3ft to sft thick occurs in mica schist at Moke Creek, Wakatipu. The ore contains from 1 1 to 55 per cent, of metallic copper, the average of Cornish ore being only 5 per cent. A lode near Collingwood, Nelson, contains 22 to 25 per cent, of copper. Another lode of the grey sulphide, found at Wangapeka, Nelson, contains 55 per cent, of the metal.

Lead ores in the form of galena occur in the Nelson district, at Rangitoto Mountain, Westland, and at the Thames goldiield. Galena also occurs at Collingwood, Nelson : galena and zinc blende at Parapara, Nelson ; argentiferous lead ore, Richmond Hill, Parapara, estimated to be worth £50 a ton ; galena with sulphide of iron and antimony carrying gold, at Wangapeka, Nelson, carrying 2(ioz of silver per ton ; galena with zinc blende, Persnverancp mine, Collingwood. The latter occurs in a band 2ft to sft thick, parallel with auriferous quartz

veins. Argentiferous galena is commonly associated with the auriferous lodes of the Cape Colville Peninsula and the Te Aroha districts. Quite recently argentiferous lodes have been found in the Pupuhi forest, Auckland.

Ores of zinc occur at Collingwood ; at Tararua creek, Thames ; zinc blende and galena, Collingwood; yellow blende, in the Perseverance mine, Collingwood ; zinc blende with galena and pyrites, at Mount Rangitoto, Westland.

Antimony, in the form of stibnite, found near the coast of Queen Charlotte Sound, Marlborough, was proved to contain from 51 to 69 per cent, of antimony. Similar lodes are found in the Shotover district, Hindon, Waipori, in the Carrick Mountains, and other places in Otago. A lode occurring some miles south of Collingwood contains 186oz per ton of silver. Antimony ores also occur at the Thames, at Keefton, and near Greymouth, associated with gold. At Endeavour Inlet (Cook's Strait), antimony is being regularly mined, smelting furnaces having been erected near the lodes for the production of star antimony. In 1888, 346 tons of the ore exported to England realised £6246. The discovery of gold in the ore from this mine has materially enhanced the value of the deposit.

Manganese occurs in the form of rhodonite (silicate of manganese) at Dunstan, Otago ; wad (hydrous oxide), at D'Urville Island; and braunite (manganese oxide), at Malvern Hills, Canterbury. Ores have also been found at Whangarei, Auckland ; at Ohariu, near Wellington ; and near Napier. The latter is a clay manganese ore, containing 44 per cent, of maganese oxide. A similar ore of better quality has been mined at the Bay of Islands for some years. Altogether, upwards of 12,000 tons, valued at over £40,000, were exported up to the end of 1885. OwiDg to a drop in the price of manganese in the Home market, operations have been suspended. A deposit of pyrolusite (manganese dioxide) has been quite recently found near Taieri Mouth, Otago. A shipment of 140 tons sent Home is stated to have been the best sample of oi e ever placed on the London market. Good samples of this ore have assayed from 88 to 90 per cent, of the pure dioxide. The ore occurs in small patches, in so irregular a manner that the cost of mining and prospecing is found to be too great to admit of the deposit being profitably worked.

A good lode of scheelite has been found near the head of Lake Wakatipu, Otago, but the .distance from a seaport is against the profitable working of the lode. Traces of this valuable mineral are particularly abundant over Otago.

Attention was first drawn to the occurrence of mineral oil in the colony in 1866, and since that time oil has been found in three different localities. These are the Sugar Loaves, Taranaki ; near Giaborne ; and at Manutahi, near East Cape, Auckland, The oil has not yet been struck in payable quantity, but the indications are very favourable

Oil shales occur in small seams in the upper portions of the coal seams. Specimens have been examined from D'Urville Island, Cook Strait ; Mangonui and Waiapu, Auckland ; Kaikorai and Blueskin, Otago ; and at Orepuki, Southland. A good variety of oil shale has also been found at the Chatham Islands. The shales- from Mangonui, Chatham Islands, and Orepuki have been distilled for oil, with excellent results.

Graphite of inferior quality has been found in several localities over the colony. It has been found in greatest quantity in the Nelson district, but it also occurs at Mai vein Hills, Canterbury, and Dunstan, Otago.

Towards the close of the year 1888 tin was discovered atStewart'slsland.both in alluvial drifts and in lodes, and at the present time a considerable amount of prospecting is being carried on. The belt of granite cou-'try extends from Stewart's Island through the West Coast Sounds and for a considerable distance inland. The rock with which tin is generally associated has been found on the mainland, so that in all probability tin may be discovered over a considerable area on the western portion of Otago.

Splendid deposits of coal occur in various parts of the colony. In the North Island seams of brown coal varying in thickness from 6ft to 50ft occur over a large area of country. Professor Hutton estimated the area of coalfield on the eastern side of the Waikato at 300 acres, oontaining 2,800,000 tons, and on the western side 7360 ncres, containing 137,000,000 tons. Seams of brown coal have been found on the Mokau river, north of Taranaki, and on most of the tributaries of the Waikato. It is probable therefore that an extensive coalfield exists in that portion of the colony. The Mokau coal formation attains a width of over two miles, and strikes north-west and south-east from Kawhia Harbour till it meets the Wanganui river in the upper part of its course. It also forms the base of the mountain ranges which have an elevation of nearly 2000 ft, and there are evidences of an extension of this same formation on the East Coast. It therefore underlies an area of at least several hundred square miles in extent. In the South Island the best known deposits of brown coal occur on a belt of county extending northward from the Clutha river almost continoasly to near Dunedin, compribing an area oC a r . least 45 square miles. In this formation there are seams of coal varying in thickness from sft to 30ft thick. The area of this coalfield is estimated at GOOO acres, containing 140,000,000 tons of coal. The same formation occurs underlying the level country to the east and south-east of the Kakanni Mountains ; and the same formation probably underlies the tertiary 'rocks of the great Canterbury plains. Brown coal and lignite are very extensively distributed throughout Otago. In Southland there are large deposits of pitch coal, which will probably be found to occur in large deposits over the whole of the province at greater depths. These deposits of brown coal and lignite are an inestimable boon to settlers in the back country where firewood is scarce. The brown coal deposits belong to the upper cretaceous period.

The bituminous coals of New Zealand arp quite equal to any imported kinds. They occur at the base of a great marine formation, underlying limestones, clays, and sandstone;: of cretaceous and tertiary age, which have a thickness of several thousand feet, the coal seams occurring wherever the for-

mation is in contact with the basement rock. The most important development of bituminous coal seams is Dn the West Coast *of the South Island, where the formation rests upon metamorphic and crystalline rocks. At Preservation Inlet and other localities on the West Coast this formation occurs, but without any coal seams that have yet been worked, until the Grey river is reached. From the Grey river northward the coal formation covers a large area of country, the seams rising with a dip of from lOdeg to 30deg from tbe sea level to heights of several thousand feet, so that the coal occurs under circumstances most favourable for working the mines. The seams vary from 16ft to 50ft in thickness, so that there must be great waste in working. At the Grey river the Mount Davey coalfield has an extent of 30 square miles. In the Brunner coal mine the coal yields vitreous coke, with brilliant metallic lustre. The engineers of local steamers estimate it 20 per cent, better than New South Wales coal for steam purposes. The same seam ia worked by the Coal-pit Heath, Tyneside, and Wallsend companies. The outcrops of coal at the Buller river occur at all altitudes up to 3000 ft above sea level, the strata resting upon a high narrow plateau that lies parallel with the coast, and extends as far north as West Wanganui, a distance of 80 miles, where the outcrop again reaches the sea level at Mokihinui. At Mount Rochfort the seams are on a high plateau 900 ft to 3000 ft above sea level, and are from 10ft to 40ft in thickness. Surveys of this coalfield prove it to contain at least 140,000,000 tons of bituminous coal of the best qoality, and all easily accessible. The Coalbrookdale mine has a magnificent seam of hard bituminous coal, 19ft thick, 1800 ft above sea level. Northward of the Buller the coal formation extends to near Cape Farewell. The formation also extends inland, for coal seams occur at the Baton and Wangapeka rivers, distant from the west coast about 30 miles, and at Pakawau, on the east coast, and at Collingwood workable coal seams have been found in cretaceous sandstone. The area of the coalfield is about 30 square miles. Somewhat similar deposits occur at Shag Point, Otago, and Malvern Hills, Canterbury. In the northein portions of Auckland there is a considerable development of the same coal formation as that on the west coast of the South Island. This formation occupies the interior of the northern district, while on the west it is overlaid and cut off by recent terbiary and volcanic rocks. The outcrop of this coal formation has been traced from a point 50 miles north of Auckland to Whangaroa Harbour, and there are indications of its continuance at Hokianga on the West Coast, The most moderate computations estimate that there are 4,000,000,000 tons of bituminous coal available in the following 1 localities : — Grey River, Buller River, West Wanganui, Pakawau, Aorere, Baton River, and Wangapeka, in the South Island ; and at Whangarei and Kawakawa, in the North Island. From the somewhat bald sketch we are enabled to give within the compass of a single article, it will be recognised that the mineral wealth of the colony is very important, and must be still more important when more fully developed. There is one other item, though not strictly a mineral product, that may be added to the mineral resources of the colony, and that is kauri gum. Although this industry has been carried on for the last 36 years, the annual exportation has continued to increase. The value of the kauri gum exported in 1887 was £362,449, and in 1888 £380,933. Licenses were issued in 1888 for the first time, and the fees amounted to £254 10s. The kauri gum ■exported to the end of 1885 was 99,479 tons, valued at £3,085,499. With this article we complete our notice of the New Zealand Mineral court, as time does not admit of a further reference to the exhibits.