154 BULLETIN 131, UNITED STATES NATIONAL MUSEUM 



Measurements of boulangerite from Independence mine 



A specimen from the Minnie Moore mine collected by D. F. 

 Hewett shows a rosette of acicular crystals of boulangerite in a 

 joint in altered wall rock from the vein associated with brown 

 hisingerite. 



A specimen from the Ontario group claims on Boyle Mountain 

 in the Warm Springs Creek district contains fibrous massive bou- 

 langerite intergrown with arsenopyrite. 



SHOSHONE COUNTY 



Boulangerite occurs as a rather constant accessory constituent 

 of the ores of the Gold Hunter mine at Mullan and at one time was 

 described by the writer, erroneously, as a new species under the name 

 mullanite. 27 It forms needles or fibrous masses imbedded in quartz 

 and siderite and thin acicular needles or felted wool-like masses in 

 small cavities in quartz which are lined with quartz or siderite 

 crystals, the boulajaagerite needles frequently penetrating the crystals. 

 The mineral is st#l gray and the streak (rubbed) is brownish gray 

 to brown. The specific gravity was determined to be 6.407. Upon 

 analysis the mineral gave the results in the following table, the iron 

 being due to siderite in microscopic rhombohedral crystals supported 

 by being pinned through by the fine needles of boulangerite. 



Analysis of boulangerite from Gold Hunter mine 

 Constituent Per cent 



Lead 53. 33 



Iron 1. 47 



Antimony. -' i. 67 



Arsenic • .04 



Sulphur .. IS. 11 



Total 98. 22 



Boulangerite, formerly called stibnite, occurs as minute tufts of 

 fibers or needles "in lead-silver ore of the Bluebird stage in one ore 



» Earl V. Shannon. Amer. Journ. Sci., vol. 44, p. 66, 1918. Much of the above data on boulangerite 

 from Blaine County has also previously been published. See Proc. U. S. National Museum, No. 2351, 

 vol. 58, pp. 589-607, and Amer. Journ. Sci., vol. 1, pp. 423-426, 1921. 



