50 BULLETIN 131, UNITED STATES NATIONAL MUSEUM 



ARSENIC (8) 



Arsenic, As. Rhombohedral. 



BONNER COUNTY 



Arsenic is known to occur only at one locality in a small prospect 

 on Vulcan Hill overlooking North Gold Creek, 2 miles from the town 

 of Lakeview, on Lake Pend d'Oreille. The mineral occurs as a 

 narrow vein in granite near the contact with Cambrian rocks. The 

 arsenic vein is parallel to the galena-bearing vein prospected by the 

 tunnel, and it is reported that where one pinched the other swelled. 

 A very little pyrite, calcite, and epidote are associated with the 

 arsenic. Polished surfaces of the arsenic, when examined with the 

 metallographic microscope, are found to be pure and homogeneous. 

 The material was collected and identified by Edward Sampson, of 

 the United States Geological Survey. 



BISMUTH (11) 



Bismuth, Bi. Rhombohedral. 



CUSTER COUNTY 



Bismuth in native form occurs in silver-white to reddish grains 

 disseminated through quartz in the Empire group of claims of the 

 Idaho-Montgomery Mining Co., in Washington Basin at the head 

 of Salmon River. Bismuthinite, barite, pyrrhotite, and pyrite are 

 associated with the bismuth, which is in part altered to bismuth 

 carbonates. 



KOOTENAI COUNTY 



Bismuth occurs in narrow quartz veins at a contact between 

 granite and slates on Beauty Bay Creek near Beauty Bay on Lake 

 Coeur d'Alene. These veins, which are several in number, cut across 

 the contact from the igneous rock into the sedimentary formation, 

 but are said to contain bismuth only where inclosed in the latter. 

 All of the quartz in the surface workings contains some bismuth in 

 disseminated grains associated with pyrite and a little bismuthinite. 

 Pannings are reported to contain also some gold, silver, and a little 

 tin. One vein of the group contains considerable masses of arseno- 

 pyrite and specular hematite. 



LEMHI COUNTY 



Fine specimens of native bismuth are reported 8 to have come 

 from one of the cobalt mines of the Blackbird district. No infor- 

 mation of the mode of occurrence of this material could be obtained. 



GOLD (13) 



Native Gold, Au. Isometric. 



The mining of gold has been in the past, and to a somewhat 

 lesser extent now is, an important industry in the State. Esti- 

 mates compiled by the United States Geological Survey give the 



s Robert N. Bell. Personal letter. 1917. 



