THE MINERALS OF IDAHO 445 



greatly resemble cemsite crystals, although they may be distin- 

 guished by their lack of twinning. In Idaho compact massive or 

 earthy anglesite has been found in a number of districts and finely 

 crystallized specimens have come from the Coeur d'Alene district 

 in Shoshone County. 



BLAINE COUNTY 



The earthy forms of anglesite are commonly present in the upper 

 portions of lead-bearing veins. They have often been reported from 

 the Wood River district and also from the districts of the Sawtooth 

 quadrangle. A specimen from the No. 3 ore shoot of the Golden 

 Glow mine consists of heavy massive ash-gray anglesite. 



CUSTER COUNTY 



Earthy or massive anglesite occurs in Custer County in practi- 

 cally all of the lead-silver deposits. Masses of this material inclosing 

 residual galena have been examined from the Hoosier and Cave 

 mines in the Bay Horse district. 



ELMORE COUNTY 



Anglesite has been noted as minute white crystals in little cavities 

 in galena which is associated with pyrargyrite and stephanite in 

 rich silver ore from the Atlanta Lode, Atlanta district. 



FREMONT COUNTY 



In the Wilbert mine, Dome district, the ore consists of dissem- 

 inated galena now mostly altered to anglesite, scattered through 

 light-gray quartzite. In places this gives way to thin lenses and 

 stringers of anglesite and galena. The mineralogy of the ore is 

 simple, galena and its oxidation products, anglesite and cerusite, 

 being the only abundant minerals. The galena is the dense variety 

 known as steel galena and the oxidation products are similarly fine- 

 grained. 50 



Gray greasy-lustered massive anglesite surrounds cores of line 

 grained galena in specimens from the Weimer copper mine in the 

 Skull Canyon district. 



LEMHI COUNTY 



Anglesite occurs sparingly in ores of the Texas, Junction, and 

 other districts. It is nowhere abundant. Pure heavy massive ash 

 gray specimens have been seen from the Latest Out mine in the 

 Texas district. 



OWYHEE COUNTY 



Anglesite is present in a number of ores from old mines in Owyhee 

 County. Specimens from the Rocksyfellow mine in the South 

 Mountain district consist of coarse grained galena coated with earthy 



10 J. B. Umpleby. U. S. Geol. Survey, Prof. Paper 97, p. 117, 1917. 



