Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/363

 at least highly suggestive. Moreover the presence of the carbonaceous matter, not in cavities in the dolomite, but imbedded in the rock itself, is a point of considerable significance to the palaeontologist, as indicating the existence of organic remains in rocks which have been referred to so old a formation as the Lower Laurentian.

The gold yielded by the pockets of the Richardson Mine usually occurred in a finely divided state, or in the form of small scales and dendritic fragments, but never exhibited distinct crystalline forms. It presented a reddish -yellow colour, and was remarkably pure. A specimen assayed in Toronto was between 22 and 23 carats fine, the native metal being thus quite as pure as the standard gold of this country. The auriferous material extracted from the pockets (consisting of the carbonaceous and ochreous substances) yielded from £3 to £4 worth of gold to the pound. How much of this gold-stuff the mine actually produced it is extremely difficult to estimate ; for whilst the workings were in the hands of Mr. Richardson, consi- derable quantities were surreptitiously carried off by parties who gained access to the mine, and were distributed to so large an extent that, even at the present time (now more than two years after the discovery), specimens may readily be purchased in the neighbourhood. It is said that upwards of 60 lbs. of the auriferous material were sent to the United States by the first purchasers of the mine, and subsequently three barrels of the same material were forwarded to New York. It is commonly supposed that the total value of the gold yielded by the pockets of the Richardson Mine was not less than £10,000.

When, however, the two deposits were exhausted the supply ceased, and attention was then directed to working the surrounding " country," where the gold exists either in so finely divided a state as to escape detection by the eye, or in combination with iron-pyrites and other metallic sulphides.

It has been said that the metal was confined exclusively to the fissure, and that it could not have been derived from the adjacent rocks, as these, if not entirely destitute of gold, are impregnated with it only to a very limited extent in the immediate neighbourhood of the crevice. Such a statement however, is, entirely contradicted by a chemical examination of rocks broken at a considerable distance from the pockets. Several assays have been made by Professor T. Bell, of Albert College, who has kindly furnished me with the results. Two specimens of dolomite from the Richardson Mine yielded respectively 9 oz. 11 dwts. 16 grs., and 4 oz. 5 dwts. 17 grs. of gold per ton of 2000 lbs. ; whilst the metallic sulphides, chiefly iron-pyrites, washed from these two specimens contained as much as 88 oz. of gold to the ton. The average value of the gold- stuff at present crushed at the mine is only about £1 per ton ; but even this is found to be more than sufficient to cover the working- expenses. It should be noted, however, that all the gold thus obtained is extracted by amalgamation ; and as the rook contains a large percentage of auriferous sulphides, it is probable that larger

VOL. XXV. PAKT I. U