THE MINERALS OF IDAHO 163 



TETRAHEDRITE (148) 



Copper sulphantimonite, 5Cu 2 S.2(Cu,Fe,Zn)S.2Sb 2 S 3 . Isometric, tetrahedral. 



The mineral tetrahedrite, commonly known as "gray copper," is of 

 widespread occurrence in Idaho as an ore mineral, some mining 

 districts having produced great quantities of ore in which it is the 

 most prominent valuable constituent. It usually contains notable 

 amounts of silver and its principal value is as a silver ore. 



ADAMS COUNTY 



Occasional bunches of tetrahedrite, locally called ''copper glance," 

 occur with chalcopyrite and small amounts of covellite, replacing 

 andesite tuffs along a shear zone in the River Queen mine in the 

 Seven Devils district. 48 



BLAINE COUNTY 



Tetrahedrite is common in the richer lead-silver ores of the Wood 

 River district, having been reported especially from the Quaker City, 

 Jay Gould, Bullion, Argent, and other mines. In the Bellevue King 

 mine it is said that a 2-foot streak of tetrahedrite was encountered. 

 The mineral usually occurs in banded veins with coarse-grained 

 galena and the gray copper often occupies the center of the vein. In 

 the Buckhorn mine on Elkhorn Hill near Ketchum, in the upper 

 tunnel, 175 feet from the surface, there was found a 2-foot vein of solid 

 tetrahedrite ore containing from 180 to 200 ounces of silver a ton. 

 Tetrahedrite is reported to have been mined from the Columbia, 

 Pilgrim, and other mines in the Sawtooth district and at Soldier 

 Mountain 9 miles north of Corral. A specimen of ore from the 

 Golden Glow mine, Rosetta district, contains massive dark gray 

 tetrahedrite, partly altered to bindhiemite, in quartzite. 



BOISE COUNTY 



Tetrahedrite, or a mineral of similar appearance, occurs occasionally 

 as a constituent of sulphide-bearing gold ores in the several mining 

 districts in Boise County. It has been noted in small masses in 

 specimens of ores from the Carroll-Driscoll mine associated with 

 sphalerite, chalcopyrite, and a little barite. Specimens from the 

 Overlook mine, Diana Mining Co., Pioneerville district, contain 

 masses of tetrahedrite up to 1 inch in diameter in quartz ore with 

 galena, sphalerite, and pyrite. 



BONNER COUNTY 



Tetrahedrite is the principal ore mineral of the Little Joe or 

 Keystone mine in the Blacktail district on the west shore of Lake 

 Pend Oreille. The mineral occurs in a gangue of manganiferous 



* f D. C. Livingston and F. B. Laney Idaho Bur. Mines and Geo]. Bull, 1, p. 40, 1920. 



