Brace on the Minerals of Litchfield* 353 



mica slate ridge, and undoubtedly had been formerly imbedded 

 in the slate. Beautiful white talc, and small crystals of sul- 

 phuret of iron, are disseminated in the mass. Specimens of 

 this mass are in almost all the cabinets in America. Smaller 

 masses have been found associated with feldspar. Small crys- 

 tals of this mineral are very common in mica slate, with stau- 

 rotide and garnet. Two of tbese crystals are often arranged 

 at right angles with each other. In Cornwall it is found in 

 small crystals in the gneiss containin"; graphite. 



Staurotide is very common and very beautiful. It is found 

 principally in mica slate, and exhibits often the cross. It most 

 generally is crystallized in four-sided prisms. 



(Quartz, of course, is common. Cornwall particularly is dis- 

 tinguished for the smoky variety. Ferruginous quartz is found 

 in rolled masses in the whole of this range. 



Petro silex, in rolled masses with ferruginous quartz, con- 

 taining veins of chalcedony and hornstone, and geodes of quartz 

 crystals, are common in Litchfield and Goshen. Sometimes 

 these masses in the interior assume the appearance of Burr- 

 stone. 



Common opal has been found in Litchfield, though rarely. 

 It was part of a mass of ferruginous quartz, with indelible 

 dendritic impression. It is very hard, and its fracture is coa- 

 choidal. 



Mica is very common. It is found green, white, and per- 

 fectly black. It generally occurs in blocks of granite. 



Schorl, in rounded crystals, is found in all the granite in this 

 range ; in radiating crystals on quartz ; and in acicular crys- 

 tals on mica slate. The large crystals are so brittle, that few 

 of them can be obtained perfect. I once found it in Litch- 

 field, near Plymouth, in prismatic crystals on earthy graphite. 



Feldspar is very common and beautiful in all the towns. It 

 is usually fonnd in rhomboidal fragments, and has a fine lustre. 

 It is blue, white, and red. Some of the granite of Torring- 

 ford is very beautiful, being composed of white and smoky 

 quartz, red feldspar, and green mica. In the porphyritic 

 gneiss, feldspar is in six-sided prisms. One small crystal of 

 adularia, well defined, has been found by E. Wilkins, Esq. 



