I9I5- No. 4- 



REPORT ON ROCK-SPECIMENS. 



Plagioclasc is highly altered, and the major portion of the sections 

 in the slice is filled with small scales of alterationproducts. According 

 to the réfringence I have calculated the plagioclase to oligoclase, An^o- 



At my request Dr. Xaima Sahlbom, Stockholm, very kindly undertook 

 the chemical analysis of this ultra-leucokratic rock: 



No. I. Aplitic-gra)ii(c. Mt. Betty. S. Victoria Lamt 



Analvst 



SiOo 



TiOo 



AI0O3 



FeoOa 



FeO 



MnO 



MgO 



CaO 



XaoO 



K.O 



BaO 



P2O5 



S . 



HoO-^°°' 



Naima Sahlbom. 



100.46 



From those figures I have calculated the following approximate mineral 

 composition : 



100.54 % 



