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The lode was, however, very narrow, and evidently only carried low average values. As seen by P. G. Morgan[1] in 1906, the outcrop was but about 6 in. wide, and in the Mining Handbook of 1887, p. 170, it is described as being from 3 in. to 6 in. in width, but widened out at one place to 3 ft. Cox, who visited the locality in 1875 or 1876, states that its character was uniform throughout, consisting of pyrites, with about 20 per cent. of galena, and remarked that it was not of sufficient value to work on its own account.[2] A sample taken by him yielded on assay only 1 oz. 17 dwt. silver per ton. About 1876 Skey made a number of analyses of samples of the ore, taken with a view to arriving at reliable data as to the true character of the lode. Nine of these assays gave results ranging from 7 oz. 19 dwt. to 45 oz. silver per ton.
It is evident that the company had no thought but to work the lode for its silver content, but even had the values in this metal been payable it is questionable if the very primitive plant that was erected would have saved them. This plant was described as consisting of a three-stamp battery, an amalgamating-barrel, and a few buddles; while an open roasting-pan made of wrought iron, about 16 ft. long and 8 ft. wide, was later added to calcine the ore before crushing. H. A. Gordon states[3] that on visiting the mine on one occasion he examined the tailings, and was surprised to see them full of quicksilver. On washing some in an old frying-pan he collected in a short time about 20 lb. of quicksilver, and from 6 dwt. to 8 dwt. of gold and silver, and he judged from this that the company could never have taken a great deal of gold or silver from the ore, and whatever there was remained in the tailings.
Even had a more suitable treatment plant been provided it is almost certain that such silver values as there were in the ore would not have proved payable, but there is a possibility that if the company had given attention to the recovery of the gold rather then the silver contents of the ore it might have met with a greater measure of success. In spite of the fact that 90 tons of the ore treated at Swansea are said to have returned 2 oz. gold per ton, and that assays made by Skey showed that some of the samples carried values up to 10 oz. 2 dwt. gold per ton, no special effort seems to have been made to save this metal. P.G. Morgan[1] states that he took a general sample from the outcrop, and one from the broken ore lying at the mouth of the drive, which yielded on assay 1 oz. 5 dwt. 6 gr. and 1 oz. 3 dwt. 22 gr. respectively. It so happens that the lode is in freehold land, and consequently cannot be investigated by the ordinary prospector, but in view of the gold values referred to some further testing of the formation seems worth while.
GOLD IN GRANITE AT MOUNT. RANGITOTO.
In his annual report for 1893 Inspecting Engineer of Mines H. A. Gordon mentions that a considerable amount of prospecting had been done on Messrs. Pollock and Bevan's property at Rangitoto, and that it had been represented they had obtained both gold and silver of a payable character in working a granitic conglomerate which crumbles away on exposure to the atmosphere. He quotes the following extract from a letter addressed by these prospectors to the Minister of Mines:—
“You may perhaps be aware that for a long time past we have been prospecting a huge belt of conglomerate, or a sort of bastard granite, which
