H. L. Wells — Sperrylite, a new Mineral. 67 



Art. YIII. — /Sperrylite, a new Mineral; by Horace L. 



Wells. 



A small quantity of the remarkable mineral which is the 

 subject of this article was sent to the writer in October of the 

 present year by Mr. Francis L. Sperry of Sudbury, Ontario, 

 Canada, chemist to the Canadian Copper Co. of that place. A 

 few tests sufficed to show that it was essentially an arsenide of 

 platinum and consequently of great interest, since platinum has 

 not been found before, at least as an important constituent, in 

 any minerals except the alloys with the other metals of the 

 platinum group. 



Since the time mentioned Mr. Sperry has furnished, with 

 great liberality, an abundance of the material for investigation 

 and has given the following account of its occurrence : 



" The mineral was found at the Yermillion Mine in the Dis- 

 trict of Algoma, Province of Ontario, Canada, a place 22 miles 

 west of Sudbury and 24 miles north of Georgian Bay, on the 

 line of the Algoma Branch of the Canadian Pacific Kail way. 

 The mine was discovered in October, 1887, and a 3 stamp mill 

 was put up for the purpose of stamping gold quartz. Associ- 

 ated with this gold ore are considerable quantities of pyrite, 

 chalcopyrite and pyrrhotite, and, at the contact of ore and rock 

 and occupying small pockets in decomposed masses of the ore, 

 there is a quantity of loose material composed of gravel con- 

 taining particles of copper and iron pyrites. It was in milling 

 this loose material that several ounces of the arsenide of plati- 

 num were gathered on the carpet connected with the stamp- 

 mill. Through the kindness of Mr. Charlton, the genial Presi- 

 dent of the Vermillion Mining Co., all of the mineral that was 

 available was generously placed at my disposal." 



It may be mentioned here that Mr. Sperry sent me, a few 

 weeks before sending the arsenide, a minute bead which he 

 had obtained in making a fire-assay for gold on an ore, consist- 

 ing chiefly of chalcopyrite and pyrrhotite, which came from 

 the same mine where the arsenide was found but which was 

 not the material in which it actually occurred. This bead on 

 examination proved to be composed largely of metals of the 

 platinum group, and, from the color of the precipitate pro- 

 duced by ammonium chloride, it was thought that it contained 

 a large proportion of iridium, but its small size prevented a 

 satisfactory examination. With this bead in mind, I expected 

 that the new mineral would contain a considerable amount at 

 least of iridium, but, strangely enough, none of this metal was 

 found in it. The material as received consisted of a heavy, 

 brilliant sand composed largely of the arsenide ; but intermixed 

 with this a considerable amount of fragments of chaJcopyrite, 



