296 



MINERALOGY 



varieties of stibnite often appear much harder than 2, from the im- 

 purities. Crystals of stibnite are at times coated with white crust 

 formed by oxidation, and at times the entire crystal has undergone 



FIG. 396. Stibnite from Lyo Island, Japan. 



oxidation, forming pseudomorphs of cervantite (Sb 2 O 4 ) after stib- 

 nite, as at Charcas, Mexico. 



In the United States stibnite occurs at Lovelocks and Humboldt 

 regions, Nevada ; in Iron County, Utah ; and in Buck County, 

 Idaho. Very little is mined, as most of the American antimony is 

 obtained in the smelting of lead ores, which contain antimony in 

 small quantities. 



The metal is used principally in the alloys, type, babbett, and 

 britannia metal. The trisulphide is used to produce the " Bengal 

 Fire/' the trioxide in the glaze of enameled ironware and in color- 

 ing glass and porcelain yellow. Many of its salts are used in medi- 

 cine. 



BISMUTHINITE 



Bismuthinite. Bi 2 S 3 . The trisulphide of bismuth is a rare 

 mineral, occurring in striated, irregularly terminated prisms. It is 

 found in small quantities in Rowan County, North Carolina, asso- 

 ciated with gold, and in the gold ores of Goldfield, Nevada. Lead 

 ores contain bismuth and most of the commercial metal is produced 

 in the electrolytic refining of lead. 



MOLYBDENITE 



Molybdenite. MoS 2 ; Sulphide of molybdenum ; Mo = 

 60, S = 40 ; Hexagonal ; Type, Dihexagonal Equatorial ; c = 1.098; 



