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off two well defined and a third more poorly 

 defined branch faults which intersect the 

 granite, along the northernmost of which 

 occur quarries 3 and 4. Here as explained 

 the tremolite ( T) beds lie dipping to the south 

 between two granite walls. Along both the 

 hanging and the foot wall, in close prox- 

 imity to the granite, have developed (by in- 

 filtration of silica from the granite ?) large 

 quantities of phlogopite, under the hanging 

 wall mixed with pink dolomite and constitu- 

 ting verdolite (^), on the foot wall altered 

 to royal serpentine [S). More or less ser- 

 pentine is found scattered through the 

 tremolite. The serpentine as usual is not 

 continuous but occurs in irregular masses 

 varying from a few pounds to many tons in 

 weight. 



One other occurrence of talc should be 

 mentioned, viz., that at 6, along the northern 

 boundary of the augite syenite. It lies on 

 tlie fault M. N. and is developed on the 

 contact of the augite syenite on the post- 

 Algonkian dolomite. The best of it consti- 

 tutes the finest qualit}' to be found in the 

 region. Its origin, as it would seem from 

 the manner of its occurrence, -is different 

 from that at the other localities. Here the 

 post-Algonkian dolomites seem to have been 

 the rocks to suffer change, the augite sy- 

 enite remaining perfectly fresh and unaltered 

 throughout, while the change from talc at 

 the contact outward towards the dolomite 

 is a gradual one. With the exception of a 

 few cubes of iron pyrites, the entire product 

 of the metamorphosis here is talc, there 

 being no serpentine and no tremolite. 



