EXPLANATION OF PLATE 26 



Fig. A. A characteristic section of gouge surrounding the soft type of pyrite. 

 It generally contains much pyrite and always shows evidence of movement in 

 the breccia fragments included in it. Natural size. 



Fig. B. Showing the metasomatie process at work in the formation of the 

 hard type of pyrite. (E) Silicified rhyolite. (S) Sulphides. Natural size. 



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