AUen and Clement — Role of Water in Tremolite. Ill 



condensation of moisture from the atmosphere, and then 

 heated. Water-elear quartz from Middleville, Herkimer 

 County. X. Y.. ground to 10 mesh and dried thoroughly at 

 110°. lost only 0'10 per cent of its weight on blasting. Trans- 

 parent crystals of adularia from St. Gothard. Switzerland, 

 treated in the same way. lost 0-12 per cent : wollastonite from 

 Natural Bridge. X. Y.. lost 0*27 per cent, and lime garnet 

 from Piedmont. Italy, lost 0*26 per cent. These losses are 

 too small to be of much interest in this connection, but the 

 remaining minerals, kupfferite. diopside and beryl, were found 

 to contain much larger quantities. 



Kv/pfferite. — The specimen examined was from Edwards. 

 X. Y.. where it occurs intergrown with the tremolite. from 

 which it was separated by heavy solutions. It is prismatic 

 and librous, straw-colored or white, has an index of refraction 

 7 = 1*62, and shows parallel extinction. A portion was ana- 

 lyzed and the results are appended. The amount of this was 

 small and the portion which was experimented on was obtained 

 afterwards and was somewhat purer. 



Calculated for MgSi0 3 

 Analysis which knpfferite approaches 



SiO., 59-29 SiO a 60 per cent 



TiCV -03 Mg6 40 " 



A1 0„ '59 



Fe"0. -29 



Feb; -06 



MnO 2-77 



MsrO... 30-98 



CaO 1-26 



Na s O -37 



K o ... -19 



F" -20 



HO 3-80 



99-83 

 O equivalent to F -08 



Heated in drv air. the mineral behaved as follows : 





Table 



V. 









Charge. 2 



grams 





Time of 

 heating 



Tempera- 

 ture 





Total loss 

 in rng. 



Loss per day 

 in mg. 



6 hours 



400 





5-9 



5-9 



3* " 



u 





5-2 



— -7 



6+ " 



it 





5-8 



+ -6 



