THE MINERALS OF IDAHO 



The angles observed by Ayres are as follows: 



Calculated 



o / // 



301 A 301 127 32 



301 A 100 26 14 



301 A 101 29 41 28 



101 A 100 55 55 28 



101 A 001 34 4 32 



205 



39 40 



Figs. 39-40.— Plattnerite. You Like Lode, Shoshone County. After Yeates and Ayres 



The optical properties of plattnernite from this lot have been deter- 

 mined by Larsen u as clouded and nearly opaque, with no notice- 

 able birefringence, refractive index for lithium light 2.30 ±0.005. 



The locality on the You Like lode is said to have produced masses 

 of the mineral up to 200 pounds in weight. 15 



In the stope above the No. 2 tunnel of the Mammoth mine at 

 Mace, plattneritc is reported to have been found occasionally in the 

 early days as masses up to 100 or more pounds in weight. Lease 

 workings in 1913 yielded small, brownish nodules and botryoidal 



•« Esper S. Larsen. U. S. Oeol. Survey, Bull. 679, p. 121, 1921. 



15 Earl V. Shannon Notes on unusual masses of plattnerite. American Mineralogist, vol. 2, pp. 15-17, 

 1917. 



