Prof. W. P. Blake read the following:
Mineralogical Notices.—No. II.
BY WM. P. BLAKE.
Kerargyrite.—Chloride of silver in remarkably fine specimens occurs in the “Poorman lode,” Idaho, associated with Proustite (light red silver ore), native silver and native gold. Sheets of the chloride are taken out of the soft clay of the vein, and are from one-eighth to one-quarter of an inch in thickness. It is also found in irregular massive aggregations of crystals, in cubes, without any modification, and over an eighth of an inch square. The color of my specimens is brown, passing into violet blue in some portions.
Proustite.—The “ruby silver” which occurs with the chloride in the Poorman lode, as above, is often in masses of several ounces, or even pounds, in weight, and it is reported to be occasionally seen in beautiful crystals, but none have yet come under my observation.
Copper Glance, Red Oxide of Copper, Native Copper.—These species are found together in the “Red Cap claim,” Klamath County, California, in serpentine. The metallic copper is seen in points throughout the massive sulphuret, and is sometimes enveloped in red oxide. Both copper and oxide are most abundant in the outer portions of the ore, as found, and they are apparently formed by the gradual decomposition of the sulphuret.
Danaite.—A cobaltic variety of mispickel is found associated with iron and copper pyrites at Meadow Lake, Nevada County, California. It is in distinct, well formed, brilliant crystals, of a tin-white color, and about a quarter of an inch in diameter. They are modified nearly as in fig. 289, Dana’s Min. This mineral gives cobalt reactions before the blowpipe, and appears to contain a large per centage of this metal. The ore is said to contain nickel, also, and is being mined for shipment.
Cinnabar in Calcite.—Cinnabar of a beautiful vermilion color is found in an unusual form in Idaho, being abundantly spread through a gangue of massive, compact limestone or marble. It is so compact and homogeneous that specimens may be cut and polished like marble. There are no evidences in the ore that I have received of the presence of other minerals, not even of quartz.
College of California, Nov. 17, 1866.
Mr. Stearns read the following: