THE MINERALS OP IDAHO 



421 



into Boulder Creek. This locality was visited in 1916 when the 

 mouth of the tunnel was partly closed by caving soil but the interior 

 was safely open. The tunnel is a drift on a vein consisting mainly 

 of coarsely crystalline white barite and pyromorphite is abundant 

 nearly throughout its length as small green to grayish or brown 

 crystals incrusting manganese-stained barite. It should furnish 

 numerous specimens to anyone venturing the rather arduous climb, 

 although it may be necessary to dig a passageway through the 

 entrance. Specimens from here are illustrated in Plates 17 and 19. 



rlEiS^ 



m 



m 



in 



in 



m 



in 



*/% % 



m 



m 



m 



x x 



136 134 



Figs. 133-136.— Pyromorphite crystals from Shoshone County 



Pyromorphite occurred associated with the plattnerite of the 

 You Like lode, now part of the Morning mine, as described under 

 plattnerite. It formed both grains and hexagonal prismatic crystals 

 up to 1 cm. long which were white or gray except where stained brown 

 or black by coatings or inclusions of plattnerite. None of this pyro- 

 morphite had the usual green color. 



In the Evolution prospect, below Osburn, pyromorphite has been 

 noted in the tunnel at the valley level where there is a considerable 

 excavation in oxidized material where the tunnel first encounters the 

 oxidized portion of the large calcite vein. The pyromorphite forms 

 tabular colorless crystals (fig. 135) in ocherous limonite or stout pale 

 green minute prisms coating the hanging wall. 



