LIME. 
243 
Saratoga County. In the town of Greenfield, a mile from the springs, apatite has been 
found in reddish brown crystals an inch or more in length, in a vein of granite, associated 
with chrysoberyl, tourmaline and garnet.* 
Westchester County. Apatite, in low six-sided prisms truncated on the terminal edges 
(Fig. 113), has been found at Anthony’s Nose. These crystals are of a brownish or yellow¬ 
ish green colour, and vary from half a line to an inch in length. They are either perfect or 
have their angles rounded, and generally present two faces broader than the other four. This 
locality is believed to have been first noticed by Dr. G. Troost.f 
This mineral also occurs at Yonkers and West-Farms, where it is associated with tourma¬ 
line and garnet; but no very good specimens have yet been obtained at these localities. 
FLUOR SPAR. 
Chaux Fluatee, Hairy. — Fluate of Lime. Cleaveland. — Fluor Spar. Phillips and Thomson. — Octahedral 
Fluor. Jameson. — Octaedrisches Flus-Haloid. Mohs. — Fluor. Kirwin and Shepard. — Fluorine. Beudant. 
Description. Sometimes transparent and 
colourless ; but more frequently white, grey, 
black, blue, green, yellow, red or brown. It 
crystallizes in cubes, which are cleavable into 
octahedrons and regular tetrahedrons, Fig. 114. 
The primary form is the regular octahedron, 
Fig. 115. It also occurs massive and disse¬ 
minated, nodular and earthy. Lustre vitreous. 
Varies from translucent to transparent. Brit¬ 
tle and easily frangible. Hardness 4.0. Spe¬ 
cific gravity from 3.10 to 3.20. Before the blowpipe, it decrepitates, and at length fuses 
into an opaque enamel. It is attacked by acids. 
When fluor spar is acted on by sulphuric acid, it evolves a gas which corrodes glass; and 
it may thus be distinguished from calcareous spar. It is also harder than the latter mineral. 
Composition. According to the researches of the most able chemists, this mineral, in its 
pure form, is composed of fluorine 48.13, and calcium 51.87 ; but is most commonly mixed 
with silica and other foreign substances. Its formula is CaF. 
Geological Situation. It occurs in veins and beds in gneiss, mica slate and clay slate, 
in various metalliferous formations of cobalt, silver, tin, lead, copper, etc.; less frequently in 
transition rocks and very abundantly in some secondary rocks, as limestone. In New-York, 
it is found in series of calcareous spar, in gneiss and in various calcareous limestones. 
Fig. 114. Fig. 115. 
Shepard. Treatise on Mineralogy, 1835. 
f Memoirs of the Academy of Natural Sciences of Philadelphia. II. 55. 
