506 



Scientific Geology. 



Crystal of Green Tourmaline in* Quartz ; Chesterfield. 



The colors of the toy. rmalines in Chesterfield are pretty uniform: 

 but in Goshen they vary exceedingly. The rubellite is rarely met 

 with there ; but the indicolite is abundant ; and this passes by numer- 

 ous gradations into green tourmalines. Of some specimens, indeed, 

 it is difficult to say whether they should be regarded as blue or green. 

 There also we meet with a yellowish green tourmaline, (No. ) 

 which is associated with spodumene. Sometimes also I have seen 

 this mineral nearly brown and even approaching to white. At Ches- 

 terfield the green variety is opaque : but some of its crystals at Goshen, 

 penetrating mica, are translucent. 



All the common varieties of feldspar are of course abundant in our 

 granite. Its ordinary color is white. But in Leverett it is blue ; and 

 often the folia are six or eight inches across. In Goshen I have met 

 with it slightly green. The siliceous feldspar, or Cleavelandite, is found 

 as already noticed, at Chesterfield, where it is commonly foliated, but 

 sometimes coarsely granular. At Goshen the same varieties occur: and 

 that which is granular exceedingly resembles sacharine limestone. In 

 Norwich it is found foliated and of a light blue color. At the other 

 localities it is always white. Mr. Andrews, preceptor of New Salem 

 Academy, finds it in foliated masses in that town of the same color. 

 It is found also at Chester.(Nos. 1535 to 1536. - 



Beryls are frequently met with in our granite: though in general 

 they are not very delicate. Perhaps the most so is a limped beryl, 

 occuring in Goshen along with spodumene, &c. It is rarely distinc- 

 ly crystalized and is full of fissures. Sometimes it is of a light rose 

 color. (Nos. 1525 to 1528 ) In Norwich and Chesterfield beryls are 

 sometimes found of a great size ; — at the latW place a foot in diam- 



