118 DESCRIPTIONS OF MINERALS. 
ores of silver, but is distinguished by being easily cut, like 
lead, with a knife; and also by affording a globule of silver 
on charcoal, by heat alone. Its specific gravity is much 
higher than that of any copper ores. 
Obs. ‘This important ore of silver occurs in Europe prin- 
cipally at Annaberg, Joachimstahl, and other mines of the 
Erzgebirge ; at Schemnitz, and Kremnitz, in Hungary, and 
at Freiberg in Saxony. It is a common ore at the Mexican 
silver mines, and also in the mines of South America. It. 
occurs in Arizona, with chalcocite, at the Heintzelman Mine, 
and in Nevada. 
A mass of ‘‘sulphuret of silver” is stated by Troost to 
have been found in Sparta, Tennessee. 
Acanthite is a trimetric sulphide of silver, Ag,S, from 
Joachimstahl ; and Daleminzite, another, from near. Frei- 
berg. 
Stromeyerite. A steel-gray sulphide of silver and copper, Ag,S 
+ Cu,S =Sulphur 15°7, silver 53:1, copper 31:°2—100. G.=6°26. 
B.B. it fuses and gives in the open tube an odor of sulphur; but a 
silver globule is not obtained except by cupellation with lead. From 
Peru, Silesia, Chili, Siberia, and Arizona. 
Sternbergite. A sulphide of silver and iron containing 338 per cent. 
of silver. lt isa highly foliated ore resembling graphite; and like it 
leaving a tracing on paper ; the thin iamine are flexible ; color pinch- 
beck brown ; streak black. From Joachimstahl and Johanngeorgen- 
stadt. 
Naumannite. A selenide of silver and lead in iron-black cubes and 
massive ; G.=8; contains 73 per cent. of silver. From the Hartz. 
Hessite. A telluride of silver, Ag, Te=Tellurium 37:2, silver 62-8= 
100. Color between lead-gray and steel-gray. Sectile. G.=838—8°6. 
B.B. in the open tube, faint sublimate of tellurous acid; on char- 
coal with soda a silver globule. From the Altai; at Nagyag and 
Retzbanya ; Coquimbo, Chili; Calaveras Co., Cal.; Red Cloud Mine, 
Colorado ; Kearsarge Mine, Dry Canyon, Utah. 
Petzite is a hessite with the silver replaced in part by gold. G.= 
8°7-9'4. Between steel-gray and iron-black. Variety from Golden 
Rule Mine, afforded Genth Tellurium 32°68, silver 41°86, gold 25:60= 
100714. Occurs at the same localities with hessite. 
Tapalpite is a telluride of bismuth and silver from Mexico. 
Syloanite or Graphic Tellurium. <A telluride of gold and silver 
(Ag, Au) Tes=(if Ag: Au=1: 1) Tellurium 558, gold 285, silver 15:7 
=100. Color and streak steel-gray to silver-white, and sometimes nearly 
brass-yellow. H.=—15-2. G.=799-8'33. Called graphic because of 
a resemblance in the arrangement of the crystals to writing charac- 
ters. From Transylvania ; Calaveras Co., California; Red Cloud and 
Grand View Mines, Colorado. 
Eucairite. A selenide of silver and copper, containing 42-45 per 
cent. of silver; color between silver-white and lead-gray ; easily cut 
by the knife. From Sweden and Chili. 
