1874.J --t) [Genth. 



tana, Dec. 26th, 1870, of wliicli I translate that part wliich refers to this 

 subject. He says : 



'^ I liave discovered the tetradyonite loJiicli I sent you in Uncle Sam's 

 Lode, in Higliland District. Two years ago I examined a fragment of 

 tetrady mite from Highland Gulch, which I found to he the sulphurous 

 variety, and icas therefore very miich surprised to find from your pamphlet 

 that the tetradymite from Highland Oulch examined hy you, was the variety 

 without sulphur. After I had repeatedly examined pieces of the said 

 mineral, I made the discovery that both varieties 0/ tetradymite are found 

 together in Highland Qihlch. This was the more interesting, since there 

 occur in it also two different varieties of gold, which fact gives pretty con- 

 clusive evidence that the gold of the Gulch comes from two diEereut forma- 

 tions. The finest gold of the Oulch originates undouMedly from the garnet 

 whicli occurs hettceen the dolomite and granite. I then examined the differ- 

 ent trial pits in the dolomite, and found in this formation at the head of the 

 Gulch in the Uncle Sam Lode the specimens inhich I sent you. In the 

 garnet rock which adjoins the Gulch on its leftside, I have not yet found 

 any tetradymite; but in a piece of garnet from the Gulch I found go\&and 

 tetradymite without sulpJiur. In all the samples of the sulphurous variety: 

 of tetradymite from the Gioleh, as well as in that from Uncle 8am'' s Lode. 

 I found a trace of selenium.'''' 



The following are the results of my analyses of the tetradymite from 

 Uncle Sam's Lode : 



100.00 100.00 



At the Red Cloud Mine, Colorado, tetradymite seems to be one of the 

 rarest minerals. The first indication which I had of it was the observa- 

 tion of a small quantity of bismuth in the analysis of one of the varieties 

 of petzite. After a great deal of search I discovered, associated with 

 pyrite and auriferous hessite, a very few minute iron-gray scales, some 

 of them with a bluish tarnish, which on examination proved to be the 

 sulphurous variety of tetradymite. 



o. Altaite. 



I have discovered this rare mineral at iico new localities — the Red 

 Cloud Mine, Colorado, and the King's Mountain Mine, Gaston Co., N. C. 

 A. p. S, — VOL. XIV. 2c 



