Spodumene and its Alterations. 



331 



oyer three per cent, of unaltered Spodumene, probably dissemi- 

 nated along the core. 



X — Cymatolite from Chesterfield. Analysis of a fragment of 

 the compact white variety, from a large pseudomorph about nine 

 inches in diameter. 



Cymatolite (Chesteefield). 



VI 



Silica, 



Alumina, 



Ferric Oxide, 



Manganous Oxide, 



Cobaltous Oxide, 



Magnesia; 



Lime, 



Lithia, 



Soda, 



Potassa, 



Water, \ 



Nitrogenous [■ 

 Organic Matter, ) 



VII VIII 



(Mean of 

 VI & VII). 



IX 



X 



58.57 



58.59 



58.58 



59.60 



58.71 



22.25 



22.32 



22.28 



22.97 



24.00 



1.79 



1.75 



1.77 



1.63 



1.39 



.15 



.15 



.15 



.45 



.11 



.02 



trace 







trace. 







.49 



.41 



.45 



.31 



.27 



.95 



.91 



.93 



.35 



.51 



.10 



.09 



.10 



.26 



.21 



9.17 



8.99 



9.08 



7.83 



7.38 



4.48 



4.47 



4.48 



5.14 



4.67 



2.04 



2.12 



2.08 



1.73 

 .32 



1.80 

 .62 



100.01 



99.80 99.90 



100.59 99.67 



In IX, on the ignition of 8.65 grammes with soda-lime, the 

 organic matter was found to yield 0.02 per cent, of ammonia 

 (N H 3 ). In this determination, as also in the similar one ap- 

 plied to Killinite, the possibility of absorption of the ammonia 

 from laboratory vapors was eliminated by using specimens never 

 so exposed, and a "blank analysis" carried on at the same time 

 supplied the small correction necessary for ammonia introduced 

 through the distilled water and reagents employed. It ap- 

 peared to be a necessary precaution to select the variety of 



