156 BULLETIN 131, UNITED STATES NATIONAL MUSEUM 



BLAINE COUNTY 



Pyrargyrite is reported to have occurred in rich ores of the Star 

 mine at the head of Star Gulch 3 miles southwest of Hailey with 

 galena and sphalerite in a gangue of quartz and calcite, and also in 

 ores of the Smoky district. 30 



BOISE COUNTY 



In the Idaho City district, on the Washington claim, 40 feet north 

 of the gold vein, pyrargyrite occurred abundantly with stephanite in 

 a quartz vein 8 inches to 4 feet in width. Near the surface these 

 mineralo were altered to cerargyrite. 31 



Pyrargyrite is an important ore mineral in the silver mines of the 

 Banner district. Specimens from the tunnel level of the Banner 

 mine show narrow seams of quartz, averaging 2 centimeters in width, 

 cutting altered granite. The quartz has grown as combs of crystals 

 from either wall and the spaces between the crystals are occupied by 

 large grains of pyrargyrite associated with stephanite and dark 

 brown sphalerite. 



CUSTER COUNTY 



Dark ruby silver occurs in small amount with cerargyrite, native 

 silver and copper carbonate, in oxidized ore of the Skylark mine in 

 the Bay Horse district and has been reported also from the General 

 Custer mine, Yankee Fork district. 32 



ELMORE COUNTY 



In the rich ores of the Atlanta lode, Atlanta district, pyrargyrite is 

 one of the most abundant minerals, being second in importance only 

 to stephanite. In a lease held by Landis & Co., in the old Monarch 

 ground where some rich ore was encountered on the surface, the vein 

 contained a streak 2^ inches wide of ruby silver with a parallel 

 streak the same width of rusty quartz containing native silver. 33 



It occurred occasionally as distinct crystals but more frequently 

 was in granular masses, either alone or mixed with stephanite (Cat. 

 Nos. 51864 and 56534, U.S.N.M.) or disseminated in minute grains 

 or larger bunches and stringers in granular quartz (Cat. No. 14759, 

 U.S.N.M.), sometimes so abundantly as to give the quartz a dark 

 color. Elsewhere it formed streaks near the walls of narrow quartz 

 veins, the centers of which were brecciated and impregnated with 

 stephanite, argentite, and stromeyerite (Cat. No. 31099, U.S.N.M.). 



IDAHO COUNTY 



Pyrargyrite is reported to occur in the Goodenough vein, Warren 

 district, with sphalerite, pyrite, tetrahedrite, and arsenopyrite. 34 



30 Waldemar Lindgren. U. S. Oeol. Survey, 20th Ann. Rept., pt. 3, pp. 199, 213. 



•i Waldemar Lindgren. 18th Ann. Rept., pt. 3, p. 689. 



32 J. B. Umpleby. U. S. Geol. Survey, Bull. 539, pp. 67, 8.5, 1913. 



» Joshua E. Clayton. Trans. Am. Inst. Mining Eng., vol. 5, Feb., 1877, pp. 468-473 



3 ' Waldemar Lindgren. U. S. Oeol. Survey, 20th Ann. Rept., pt. 3, p. 248, 1900. 



