240 Lead Mines, &c. of Hampshire County, Mass: 
field it is generally of that kind which is called milky quartz j 
where the mica is disintegrated, these nests fall out and lie 
scattered upon the ground. In one instance, in Chesterfield; 
I noticed an immense boulder of it, full 10 or 12 feet in dia+ 
meter, 
There is a variety of mica slate, seen only in Chesterfield, 
containing cyanite and garnets of an enormous size. It 
seems to be a stratum that has been broken up, and is now 
scattered, here and there, in specimens of all sizes, up to 
feet in diameter. In going from Chesterfield to Williams- 
burgh, this variety is first noticed, one mile east of Chester- 
field meeting house, in a large block, lying by the road side. 
Beginning at this block, and running one mile north, we fin 
the boulders, here and there, in a state of decomposition ;— 
some of them have wasted almost entirely away, leaving the 
nests of quartz and scales of mica in their stead: he mica 
scales, of which this rock is chiefly composed, are of all co- 
lours, some being a beautiful straw colour, a dove brown, or 
an orange yellow, while others are a grass or a j 
black, and are often several inches in surface, and so loosely 
‘Srains, or small garnets in immense numbers. 
: With garnets, there is cyanite and quartz in this 
eae TE : : . | 
~ 1, +e quartz is of a milk white, often transparent, or 
limpid, and in nests of all sizes 
