THE MINERALS OF IDAHO 435 



BINDHEIMITE (670) 



Hydrous lead antimonate, approximates 



the formula 2PbO.Sb 2 5 .xH 2 0. Amorphous. 



Bindlieimite is a common mineral formed by the oxidation of 

 antimonial sulphides in lead-bearing ore bodies. It is most frequently 

 some shade of yellow in color, although other colored varieties are 

 known, and in texture it varies from a soft friable pulverulent ocher 

 to compact opaline material. The bindlieimite, in some cases is the 

 result of alteration of lead sulphantimonites, as boulangerite and 

 jamesonite and then usually has a fibrous structure inherited from 

 the parent mineral. It commonly results from the alteration of 

 tetrahedrite-galena ores in which the antimony is furnished by the 

 tetrahedrite and the lead by the galena. Most of the Idaho occur- 

 rences have had this origin. The occurrences which have been 

 noted in the State are described separately below. It is noteworthy 

 that bindlieimite contains its antimony in a form very hard to 

 reduce so that, by ordinary blowpipe methods, this element is very 

 hard to detect and ocherous bindheimites from Idaho have previ- 

 ously been called massicot, in error, by the present writer as well as 

 others. Massicot is not definitely known from the State. The 

 pulverulent yellow bindlieimite is commonly called " chlorides" by 

 Idaho miners when yellow, or "bromides" when stained blue or 

 green by copper. 



BLAINE COUNTY 



Bindlieimite was probably common in oxidized lead-silver ores of 

 the Wood River country and elsewhere in Blaine County. A speci- 

 men from the bins at the No. 2 tunnel of the Golden Glow mine in 

 Boulder Basin contains bindlieimite occurring sparingly as an alter- 

 ation product of boulangerite. 



CUSTER COUNTY 



Bindlieimite is common in the Bay Horse district in Custer County. 

 A specimen from the Ramshorn mine contains yellow-green waxy 

 bindlieimite occurring with malachite and azurite as an oxidation 

 product of tetrahedrite containing granular galena. A small amount 

 of waxy yellow bindheimite occurs with cerusite and galena in quartz 

 in a specimen from the River View mine. A yellow to greenish- 

 yellow earthy pulverulent mineral associated with massive cerusite 

 from the Cave mine is probably bindheimite. Yellow powdery 

 masses of this mineral occur with malachite and anglesite as an 

 alteration product of galena-tetrahcdrite ore from the Hoosier 

 group, above the Beardsley mill in the Bay Horse district, and com- 

 pact waxy yellow material occurs sparingly in quartz with linarite 

 in a specimen from the Pacific claim. Compact bindheimite, green- 



