■382 



C. A. SUSSMILCH AND W. G. STONE. 





Per cent, 



BaO ... 



... 0-04 



SrO ... 



f present 



Li 2 ... 



... absent 



V 2 0,... 



... absent 



CuO ... 



Per cent. 



trace* 



100-39 



* Trace less than 0-01% 



Specific gravity 2*688 

 f Spectroscopic reaction only. 



Noi 





Per cent. 







Per cent. 



Quartz 



.. 34-86 



M agnetite 





1-86 



Orthoclase 



.. 12-79 



Ilmenite 





0-61 



Albite 



.. 29-34 



-Apatite 





0-34 



Anorthite 



.. 12-51 



H 2 0, C0 2 



etc. 



4-41 



Corundum 



.. 0-41 









Hypersthene . . . 3*18 



100-31 



Class I. Persalane. 

 Order 3 Columbare. 



Magmatic name Alsbachose. 



Rang 2 Alsbachase. 



Sub-rang 4 Alsbachose. 



Bearing in mind that the lime in the anorthite and hypers- 

 thene molecules, is represented in the rock mainly by 

 calcite, which is in part due to infiltration, the plagioclase 

 must be essentially a soda variety. 



Another example of quartz-felsite, also from the road- 

 cuttings at the head of Hinchman's Creek (Slide N 2) shows 

 the following points of difference from that just described: 

 (1) the quartz phenocrysts predominate largely over the 

 felspar. (2) The comparative paucity of this rock in plagio- 

 clase, indicated by the much lower percentage of soda 

 present, the amounts as given in the analyses being respec- 

 tively (x 894) 3*47 per cent, and (N 2) 0*98 per cent. (3) 

 Flow structure is more marked and there is a much greater 

 development of sericite which forms a plentiful constituent 



