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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 these crystals are often arranged 
at right angles with each other. In Cornwall it is found in 
small crystals in the gneiss containing graphite. 7 iy 
 Staurotide is very common and very beautiful. _ It is found 
principally in mica slate, and often exhibits 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, aud 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 a part of a mass of ferruginous quartz, with indelible 
dendritic impressions. It is very hard, and its fracture,is, con- 
choidal. hid ie 3 cee gibszs 
Mica is very common. It is found green, white, and per- 
fectly black. It generally oceurs in blocks of granite. 
- Schorl,; in rounded crystals, is found in all the granite in this 
range ; -in radiating crystals on quartz; and in a acicular crys- 
tals on mica slate. The large crystals are so brittle, that few 
of them. can be obtained perfect. 1 once found it in Litch- 
field, near Plymouth, in prismatic crystals on earthy eraphite. 
Feldspar is very common and beautiful in all the towns, It 
is usually found 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 prism. One small crystal of 
aria, well defined, has been found by E. Wilkins, Esq. 
