THE 



CANADIAN RECORD 



OF SCIENCE. 



vol. vi. april, 1894. no. 2. 



On the Formation of Pegmatite Veins. 



By Prof. W. C. Brogger, of Stockholm, Sweden. 



(Translated from ''Die Mineralien der Syenitpegmatitgiinge der 

 siidnorwegischen Augit und Nephelinsyenite," by Nevil 

 Norton Evans, M. A. Sc). 



(Concluded.) 



This hypothesis is supported by a large number of facts ; 

 in what follows, will be given a resume of the more important 

 of these. 



1. As far as the principal minerals are concerned, the 

 composition of pegmatite veins corresponds, with great 

 uniformity, and frequently over long distances, to that of 

 the allied eruptive rock of the magma of which the veins 

 are generally the final ejections. With certain special iso- 

 lated exceptions, their composition is quite independent of 

 the nature of their wall-rock. 



As examples, we may again cite the norite pegmatites 

 occurring in the norite and labradorite rocks of the large 

 norite-labradorite district of the south-west part of Nor- 

 way ; the augite syenite pegmatites of the region round 

 Fredriksviirn, corresponding to the augite syenites; the 



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