C.—9

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not have been brought from any considerable distance,, although in the creek itself we found nowhere a quartz vein in situ. On the slope of the hills I saw large blocks of quartz lying, which from all appearances originated from ' reefs ' or veins, that—according to the statement of Mr. Heaphy —protrude on the top of the dividing-ridge in various places like walls, 8 ft. to 10 ft. high and 10 ft. to 20 ft. thick. I much regretted the inclemency of the weather at the time, which frustrated our intention to examine these quartz reefs more closely. It is worth mentioning that gold was also found on the creeks flowing from the east side of the Cape Colville Range on Mercury Bay into the sea; on the Arataonga, Waitekauri, Cook's River, and others. The traces of gold, therefore, seem to extend over a larger district, and the Coromandel goldfields —such was my opinion in 1859 —bid fair to grow into importance in future years, when the country, as yet covered with dense woods, shall have become more accessible, when the auriferous-quartz reefs themselves shall have been discovered, and the difficulties which the Natives have hitherto opposed to every undertaking on a more extensive scale have ceased."* The volcanic rocks of the Cape Colville Peninsula were regarded by Hochstetter as forming part of the older series of volcanic formations, as given at page 66 of his work on " New Zealand " above referred to. The rocks of Beeson's Island and the shores of Coromandel Harbour he mentions as being formed of trachytic rocks : " The coast consists of nothing but trachytic breccia and tuff, in the most varying colours, and in the most different state of decomposition " ; and, referring to the more interior parts of the Coromandel district, he says, " The Coromandel gold originates from quartz reefs of crystalline structure, belonging to a Palaezoic clay-slate formation, of which, under the cover of trachytic, tuff, and conglomerate, the mountain-range of Cape Colville consists." When Hochstetter visited Coromandel, gold-mining was at a standstill, and the state of the weather at the time prevented the making of any examination of the interior parts of the country. Mining in the Coromandel district languished for some years, but in October, 1861, Coromandel again became the scene of mining operations, and a fresh impetus was thus given to prospecting and mining, which speedily made itself felt in the northern part of the Peninsula, and the district was proclaimed a goldfield in June, 1862. In the meantime the district had been visited by Sir James Hector, who in his report " On the Geology of the Cape Colville District," 1870, says : — " My first visit to Coromandel was in June, 1864, at which date the mining operations were being conducted with considerable activity, but confined to a very limited area. The following notes, made at the time, indicate the state of our knowledge of this mining district at that date, and before additional experience of the manner in which the mineral lodes in other parts of the Colville Peninsula had been obtained. " On entering the harbour, the rocks on each side are seen to be stratified, and dipping to the westward from the land, but rising again to the north and south, and, on landing at Beeson's, on Wanganui Island, were found to consist of trachyte, tufa, and conglomerate. The included fragments of trachyte, often of large size, are porphyritic with crystals of hornblende. In some places beds of compact trachyte occur, but this is probably only a variety of the tufa which has been more consolidated, or composed originally of finer-grained material. These tufas decompose freely to a ferruginous earth, which is sometimes bleached white, and frequently traversed by veins of quartz. " Where excavations had been made in this formation in search of auriferous reefs, the rock appeared to be a mottled purple trachyte porphyry, traversed by bands of felspathic clay—probably decomposed dykes, which contain masses and veins of crystallized quartz—also, a soft vein in the same description of rock, Bin. to 10in. in width, containing masses of horny quartz. These veins underlay to the east, and strike north-north-east. No gold has been found in any of these veins. "At Keevin's Point, a spur of the hills terminates in a bold ridge composed of light-grey tufaceous porphyry, containing iron-pyrites. The hill has been prospected in all directions by the miners, and the existence of two distinct reefs established. These consist of a banded quartz of a blue colour, with cavities lined with crystals. The rock appears to be originally a clay-stone porphyry, in which veins of segregation have been formed. The rock contiguous to these veins has been converted into a mottled pipeclay, stained with oxides and carbonate of iron. No gold has been found in these veins, which strike north 35° east, and dip eastward at 40°. [ "The chief diggings are up Driving Creek, two miles from Keevin's Point, in a north-east direction towards the highest point of the range. [Kapanga Mine?] Only one mine was in active operation (in 1864), having a five-stamp battery at work crushing a blue sub-crystalline quartz. The main reef is 6 in. to 8 in. thick, strikes north-by-west, and dips to the west at 45°. Since the new batteries began work they had crushed 40 tons, with a yield of 1,120 oz. Three shafts were sunk the depth of 150 ft., and one main level put in on the reef for 200 ft. Two other 'leaders' occur parallel with the main reef, with 30 ft. and 40ft. of white rotten rock between. The lower or east side of the main reef is a very hard fine-grained breccia, charged with pyrites. Each leader consists of a band of bluish mullock, containing strings and nodules of quartz, generally quite detached, and frequently very auriferous. From practical trials by Mr. Ninnis, the pyrites obtained as tailings from the mill contains gold in the proportion of 7 dwt. to the pound. It is not established, however, that the pyrites from the rock contains this large proportion, or only that which is derived from the vein-stuff put through the mill. As much of the quartz is evidenty rich to the eye, these portions are selected and crushed separately as specimens. A crushing of 1,7061b. of such specimens gave 2,198 oz. of gold. The rest of the ore from which the above specimens were picked weighed 100 tons, and yielded in the proportion of 4 oz. per ton.

* "New Zealand," by Hochstetter (English edition), pp. 94-98. f Keevin's Point and the adjacent hills, now the scene of active mining operations, are in this report regarded as formed of volcanic ash and fine-grained breccias of an andesic type, and as belonging to the Kapanga group of volcanic rocks, extending north along the coast-line to Paparoa, south to Preece's Point, and inland to the lower slopes of the Tokatea and Success Ranges.—A. McK.