THE MINERALS OF IDAHO 467 



loosely to indicate isomorphous mixtures of the two end members 

 which contain both iron and manganese. The Idaho materials de- 

 scribed below as wolframite are those whose composition has not been 

 determined and they may include some ferberites or hubnerites. 



WOLFRAMITE (812) 



Iron-manganese tungstate (Fe,Mn)O.W03. Monoclinic. 



The occurrences of minerals of the wolframite group in Idaho which 

 are not mentioned under hubnerite or ferberite are as follows: 



BOISE COUNTY 



Wolframite occurs as reddish to brownish black cleavable masses 

 disseminated in quartz from the Horse Fly prospect and as very black 

 indistinct friable material in vuggy quartz coated with a thin layer 

 of chalcedonic silica in specimens from the Merry Blue mine, both 

 in the Deadwood Basin. 



BUTTE COUNTY 



Wolframite occurs in a quartz vein in the Independence claims 

 near the summit of Granite Mountain 20 miles from Arco on the 

 Hailey-Arco trail. The vein, which is at the contact between 

 diorite and a siliceous rock, averages 6 feet wide and is made up of 

 crystalline drusy quartz heavily stained with iron and manganese. 

 The wolframite occurs as occasional scattered black crystals and 

 bladed masses. 75 



LEMHI COUNTY 



Large plates of wolframite occur in massive quartz in specimens 



sent to the United States Geological Survey by Fred Gerdes of 



Leadore. Idaho. 



HUBNERITE (813a) 



Manganese tungstate, MnO.W0 3 . Monoclinic. 



Hubnerite has been mined in two places in Idaho, one of which has 

 made a notable production of tungsten ore. 



BONNER COUNTY 



Hubnerite occurs in veins near Talache on the west shore of Lake 

 Pend Orielle. These deposits have been examined by Mr. Edward 

 Sampson of the United States Geological Survey and will be described 

 in a report by him which is now in preparation. 



LEMHI COUNTY 



Hubnerite occurs in sufficient abundance in the Blue Wing district 

 in Lemhi County to have been mined to some extent as a tungsten 

 ore. 78 The hubnerite has been mined principally in the Ima mine 



« D. C. Livingston. Univ. of Idaho School of Mines, Bull. 2, p. 28, 1919. 

 ™ J. B. Umpleby. U. S. Geol. Survey, Bull. 528, pp. 73-74, 1913. 



