110 BULLETIN 131, UNITED STATES NATIONAL MUSEUM 



ELMORE COUNTY 



In the Neal district a little sphalerite occurs with pyrite and galena 

 in the primary ore of the gold veins. A sample of clean sphalerite 

 yielded 1.4 ounces gold a ton on assay. 81 In the Pine Grove and 

 Rocky Bar districts sphalerite is of similar scattered occurrence in 

 the primary ore of the sulphide-bearing gold veins. 



IDAHO COUNTY 



Sphalerite occurs in a large number of mining districts in Idaho 

 County, but mainly only as scattered grains in gold quartz ores. 

 A typical specimen of ore from the Mallard Creek property of W. 

 vSendke in the Dixie district shows sphalerite as sparse light brown 

 grains with galena in quartz; and one from the Black Pine mine, 

 Elk City district, has cleavable grains of dark brown sphalerite 

 disseminated in quartz with galena, pyrite, tetrahedrite, and free 

 gold. 



LEMHI COUNTY 



Sphalerite is widespread in occurrence in the various mining 

 districts of Lemhi County, but nowhere in sufficient amount to 

 constitute an ore of zinc. As much as 10 per cent of zinc, probably 

 mostly in the form of secondary minerals derived from sphalerite, 

 appears in some of the lead-silver deposits. In the ores of the Blue 

 Wing district black sphalerite is commonly associated with hubnerite, 

 with which it is likely to be confused. Its characteristic light gray 

 streak, however, serves to identify it. 



OWYHEE COUNTY 



In the Silver City, De Lamar, and Flint districts sphalerite 

 occurs in the silver ores, usually as sparse grains in comb quartz 

 with rich silver-bearing sulphides. A specimen labeled as from the 

 Banner mine, Silver City district, contains sphalerite in masses up 

 to 1 centimeter in diameter with chalcopyrite disseminated in white 

 quartz. This sphalerite, which shows good cleavage, is light gray 

 in color, almost as white as the Franklin furnace cleiophane, and 

 has a white streak. A specimen of sulphide gold ore from the Bergh 

 mine, 11 miles north of De Lamar, consists of coarse black sphalerite 

 intergrown with galena and pyrrhotite. In the South Mountain 

 district sphalerite is common in the ores associated with galena and 

 other sulphides. A specimen from the Bay State mine shows very 

 black sphalerite intergrown with arsenopyrite. 



" Waldemar Lindgren. U. S. Geol. Survey, ISth Ann. Rept., pt. 3, p. 702, 1S96. 



