EEL 
Localities of Minerals. 237 
Hexagonal crystals of mica.—They are in granite. As I 
did not notice them at first, I cannot tell where the granite 
was obtained, but believe it was from Chester or Westfield, 
on the granite ridge. Some of the crystals are small, not 
more than one tenth of an inch on a side and almost regular 
hexagons. Others are larger, and have —— sides.— 
ine real size of them is here given. 
No. be No. 2. s ia : 
The sides are 
nat bes ry Oe oO. ra Enlarged. 
some of the ‘oAyiis much resemble those — 4 
you mentioned in the Journal from Porto ————_—* 
Rico. It is probable that other “specimens of titi oni 
An attempt to measure the angles of No. 1 
“G=S1229, 61269, c==1120, © d=—=121°, and 
a 820.°'The sum’ is 721°, and should be but 720°. 
e above angles may therefore be taken as very near the 
ttath. 
In No. 3, the angles were as follows, a==116°, 51249, 
CST 29°9; d=112° » e==28221°, and n—117°, being ae, 
7203°, and approximating nearly to the truth. I do 
ee the angles are very accurate, for I had no Fite 
ams of measuring them. In some of the crystals, the 
sada are more unequal than in No. 3. 
~ In some rhombic spar, containing the new mineral, Bru- 
mai de from Sparta, New: T found several hexagonal crystals 
mica. 
gt of ae in dolomite, from Great Barring- 
These crystals are much compressed, and the diedral 
ie Sent odie: so that they become bladed crys- 
tals. They are from one half inch to two inches, or more, in 
Jength, ania some of them three fourths of an inch in breadth. 
They are found in hard rocks cf dolomite, above ground, 
and very abundantly, in the very friable dolomite, under the 
“surface of the earth. The fibrous and acicular varieties of 
tremolite are abundant in the South part of this county. 
rown Spar from Leicester, . on Genesee river.— 
‘The crystals are rounded, or lenticular, and often so taal 
ed, as to have a scaly appearance—colot w, dark .brown 
Vou /ALNo, 2. 31 
