294 
DESCRIPTIVE MINERALOGY. 
Silica,. 51.00 
Lime,.... 21.00 
Magnesia,. 11.50 
Alumina,. 3.50 
Peroxide of iron, with a trace of manganese,.. 11.53 
Water,... 1.00* 
Lamellar pyroxene of a dark colour, and exhibiting cleavage in the direction of P, is found 
at many of the localities of magnetic iron ore in the town of Monroe, as at the Forest of Dean 
mine, the Rich iron mine, Long mine, Mountain mine, Patterson mine, Sterling mine, Cross¬ 
way mine and O’Neil mine. There is a great deal of similarity in the characters which the 
mineral presents at these different localities. 
The granular variety coccolite is also exceedingly abundant in this county. In the town 
of Monroe, a mile west of Coffee’s hotel, it is in small grains, perfectly black. Near Green¬ 
wood furnace, it is light green and translucent, and often in large grains which admit of 
cleavage. Again, in the Forest of Dean, it is black; and the same character will apply to 
that which occurs at the Forshee and O’Neil mines, as well as that from Bull’s pond in the 
same town. It is also found at Rocky hill in Warwick, and in the town of Cornwall, four 
miles west of West-Point. 
At some of the above localities, pyroxene is found in such abundance as to constitute rocky 
masses ; and there is often observed at, or near, the same spot, the crystallized, the lamellar 
and the granular varieties, passing into each other, and varying in colour, so that it becomes 
almost impossible to indicate the line of distinction between them. 
Putnam County. At Hustis’ farm in Phillipstown, there is a variety of pyroxene which 
has been called diopside. It is translucent, has a light green colour, lamellar structure, and 
a glistening surface. It sometimes contains small crystals of pale green apatite. Associated 
with it are white, rose-coloured and green coccolite. The whole is contained with serpentine 
and other allied minerals in white limestone. The white coccolite was formerly considered a 
new variety. It is made up of grains of various sizes, and resembles dolomite. Pyroxene, 
crystallized in eight-sided prisms, has been found at Coldspring in this county, where other 
varieties, similar to those just noticed, also occur. 
About two miles south of the village of Carmel in the town of Southeast, there is a dark 
green, almost black, coccolite, associated with crystallized epidote, hornblende, etc. It is not, 
however, abundant. Pyroxene also occurs on Townsend’s farm, about half a mile north of 
the preceding locality. 
In the dolomitic beds near Patterson, crystallized white pyroxene is very abundant; so 
much so, that in some places it greatly injures the value of the limestone for the uses to which 
it is ordinarily applied. In some places, the surface of the little elevations of the rock is 
Journal of the Academy of Natural Sciences of Philadelphia. III. 68. 
