﻿298 Canadian Record of Science. 



the granite has been * decomposed to a soft greenish 



siUcious matter, which is impregnated with large crystals 



y of pyrite. In all fault- 



,-^/^v .,* ing and sudden ceasing 



^" ^ .i^fst^^^S^^^''" ^^ ^^^^ ^^® bodies there 



,.r<'jjpjr0:^tj^ is little evidence of 



/rU<^Uj'1^^T--^^'^>'^ll-/^' vein matter or other 



r-it:^y^it^i?fJoH indication of which way 



'^^tM^fftJ [ H-^ ' >■■ ^^^^ continuation may 



^p^jp^" ""^ be found. 



' ?i**^ Aside from displace- 



ments and rapid varia- 

 tions in width, these quartz veins show great persistence 

 both in reappearance and in mineralization. 



The mineralization of these /eins is sporadic, or chute- 

 like, with a tendency to banding where the ore body is of 

 regular width. Usually the enlargements give rise to a 

 more cellular and comb-like structure, and in such places 

 the richest minerals are found. 



KiOA Horses, such as shown 



J o.r»r..f<^ ^ in Figure 4, are common.. 



y^i-^j^f^^^^^^^'-^""''^"' ^ The one figured shows 



K <'^^7^^^^^£5^^^—'^^° "'*"«* marked evidence of great 



S* ' ' ,.--iri^???^^^^j7?^^ crushing, probably an- 



' '^r^*^^'^ terior to the forming 



of the vein matter. An analysis of this horse gave : — 



SiO^ 71-70 



AlA l«-25 



FeA 3-18 



MgO. 212 



CaO 3-36 



Total 98-61 



The alkalies were not determined, but are evidently 

 much lower than the normal granite. 



