Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/364

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returns would be yielded by a metallurgical treatment better adapted to the character of the ore.

In the same township as the Richardson Mine, gold- ores have recently been worked at several localities. The Madoc Gold- Mining Company's shaft on lot seventeen in the seventh concession of Madoc was sunk on a quartz lode, coursing through gneiss N. 15° W., and dipping about 60° W. Very little free gold was visible ; but the iron-pyrites disseminated through the quartz was apparently auriferous. Samples of vein-stuff from near the surface yielded about £12 10s. of gold to the ton, and at a depth of between 30 and 40 feet Professor Chapman found the quartz to contain 3 dwts. 12 grs. of gold, and 1 oz. 11 dwts. 12 grs. of silver per ton ; but at a depth of about 60 feet the vein became entirely barren of gold.

At the Empire Mine, also situated in the township of Madoc, both gold and silver have been obtained from a vein-stone containing arsenio-antimonial grey copper-ore, together with mispickel, iron-pyrites, and bitter-spar. According to Professor Bell's assay, the grey copper-ore contained 8 oz. 4 dwts. of gold, and 331 oz. of silver to the ton of 2000 lbs., the value of which would be £95 ; and this result was confirmed by Dr. Sterry Hunt, who found that the dressed ore, when holding one-fourth its weight of vein-stone, yielded 9.7 oz. of gold, and 120. oz. of silver to the ton of 2000 lbs.

In the adjacent township of Marmora auriferous quartz has been worked at the Feigle Mine, opened on lot sixteen in the eleventh concession. The gold is here associated, as in so many other gold- bearing localities, with a vitreous quartz more or less stained with hydrous peroxide of iron. Mr. Bell has found that one sample of this quartz yielded, by amalgamation, 3 oz. 13 dwts. 8 grs. per ton, whilst another portion contained 7 oz. 15 dwts. 12-1/2 grs. per ton. [A specimen exhibited from the Feigle Mine showed the free gold imbedded in a large prismatic crystal of liver-coloured Eisenkiesel, or quartz charged with hydrous peroxide of iron.]

At the Barry Mine, in the township of Elzevir, a dark crystal- line limestone is crushed for gold. The mean of four assays of ore, discovered in this township by Mr. Smallfield, yielded gold to the value of nearly £8 per ton of 2000 lbs.

From the township of Hungerford, quartz containing much iron- pyrites has been found to contain both gold and silver, probably in association with metallic sulphides.

Nothing would be easier than to considerably extend this list of gold-bearing localities. Indeed it appears that the metal is distributed, in greater or less quantity, through most of the schistose rocks of the gold-mining region ; for I have invariably found that these rocks yield, on assay, a notable amount of metallic sulphides more or less auriferous. Probably the most advantageous mode of treating these sulphides would be to smelt them to a rich regulus, which might be then exported to England for extraction of the gold.

Note. — The following assays of gold-bearing rocks, from the Quinte gold-mining . district, by Professor Chapman, of University