THE MINERALS OF IDAHO HI 



SHOSHONE COUNTY 



Shoshone County contains large amounts of sphalerite. This 

 occurs as a constituent of the ores of the veins which have been 

 mined for lead and silver, although the proportion of sphalerite in 

 the ore varies markedly from vein to vein, some mines containing 

 very little zinc associated with the galena, and there are a large 

 number in which the zinc sulphide nearly equals galena in amount 

 and a few in which sphalerite is the most abundant mineral and galena 

 is subordinate. The production of zinc in 1916- from this region is 

 reported as over 86,000,000 pounds of metal, or about one-fourth 

 as much zinc as lead. 



The sphalerite is practically all massive and of a dark brown color 

 and resinous luster. The size of grain varies but is usually similar 

 to that of the associated galena. In the Amy Matchless claims on 

 Pine Creek a few reddish crystals occur in minute vugs, several ruby 

 red crystals of small size occurred in a crack in ore from the 1,600-foot 

 level of the Greenhill- Cleveland mine at Mace and a few honey 

 yellow tetrahedral crystals were noted in a specimen from the Temby 

 stope of the Bunker Hill mine. These constitute the only known 

 free crystals from the district. The color of the mineral in the Coeur 

 d'Alene region is chiefly a uniform dark brown, although coarser 

 reddish-brown material lias come from the Success mine, a little 

 honey yellow of coarse grain has been found on the No. 13 level of 

 the Bunker Hill mine, and a peculiar gray fine-grained sphalerite 

 occurs in some quantity associated with similar galena in calcite and 

 quartz in ore from the Hamburg-American claim on Little North 

 Fork of Coeur d'Alene River. 



The mines along Canyon Creek contain variable amounts of 

 sphalerite. It is common in the Hercules but occurs for the most 

 part in segregated bunches. The Hecla vein is relatively free from 

 sphalerite. In the Marsh and the now abandoned Tiger-Poorman, 

 Standard-Mammoth, and Greenhill-Cleveland veins the sphalerite 

 was relatively unimportant in the upper levels but seemed to become 

 increasingly abundant with depth. The Frisco ore body contains 

 much sphalerite. 



Near Mullan sphalerite is a more or less constant accessoiy in the 

 Gold Hunter ore and is abundant in the Morning mine while in 

 the adjoining Star property the ore consists of an intimate inter- 

 growth of galena and sphalerite. 



On Ninemile the deposits are for the most part essentially zinc 

 mines, galena being very subordinate. The Success (Granite) has 

 mined a very irregular mass of sphalerite ore containing the sphalerite 

 in association with garnet, mica, chlorite, and other contact meta- 

 morphic silicates, at the contact of an intrusive mass of quartz mon- 

 zonite against the inclosing slates. The Interstate- Callahan, one 



