Minerals in Granite. 



505 



calities. In Chester it is found in large crystals : also in connection 

 with the green and red varieties in the northwest part of Goshen, as- 

 sociated with several other minerals. 



The most noted locality of green and red tourmalines is in Ches- 

 terfield, on land of Mr. Clark. They are contained in an enormous . 

 vein'of granite in mica slate, which corresponds nearly in direction with 

 the layers of the slate. This granite is crossed obliquely by a vein, 

 varying in width from six to eighteen inches, of smoky quartz and 

 silicious feldspar : or rather, the quartz forms the central part of the 

 vein, and the feldspar lies on each side of the quartz : the green red 

 and blue tourmalines, with schorl and sometimes beryl, passing 

 through the feldspar and the quartz. This cross vein has been laid 

 open from twelve to twenty feet by blasting; and it is really, in the 

 eye of a mineralogist, a splendid object. I do not see that there is 

 any prospect that it will soon be exhausted ; although I doubt wheth- 

 er as fine specimens are now obtained from it as formerly. 



The crystals of green tourmaline and rubellite at this locality oc- 

 cur in rounded prisms, deeply striated longitudinally. They have 

 been found an inch in diameter, but generally they are much less, and 

 the red are rarely more than one quarter of an inch : sometimes they 

 exhibit triedral summits. It is very common for the rubellite to be 

 enclosed in the green crystals, and sometimes a thin layer of talc in- 

 tervenes between the inner and the outer crystals. Col. Gibbs found 

 three of the red crystals in one instance aggregated together, and en- 

 closed by one of green. The green crystals also sometimes embrace 

 indicolite, and sometimes indicolite encloses the green tourmaline, as 

 niaybeseenby the specimens Nos. 1 521 1522 & 1524. The green tour- 

 malines as well as the rubellite are sometimes entirely distinct from 

 each other ; especially when they are contained in the quartz. In some 

 instances I have met with marks of rather singular disturbances 

 which took place while the green tourmaline was crystalizing in the 

 quartz. The quartz is fissured into somewhat parallel laminae, and 

 together with portions of the crystal, has been subjected to a sort of 

 echellon movement, while in some places it has been so compressd as 

 almost to disappear. This last circumstance seems to indicate that 

 the disturbance took place before the crystalization was completed. 

 The following sketch is intended to represent this phenomenon. 

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