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DESCRIPTIVE MINERALOGY. 
NEMALITE. 
Nemalite. NuttaU, Phillips, Shepard and Dana. — Siliceous Hydrate of Magnesia. Thomson. 
Description. Colour white, greyish and bluish white. It occurs in the form of elastic 
fibres, usually parallel, sometimes curved, and which are easily separable. It closely resem¬ 
bles asbestus. Lustre pearly. Translucent or opaque. Hardness about 2.0. Specific 
gravity from 2.35 to 2.44. By exposure to a red heat, it is rendered brown, gives out 
water, becomes brittle, and is easily reducible to powder. It, however, still retains its 
fibrous structure. Soluble in acids without effervescence. 
This mineral closely resembles asbestus, and some varieties of Dr. Thomson’s stellite. 
The action of the blowpipe, and of acids, will serve to distinguish it. Asbestus does not 
become brown or brittle before the blowpipe, like nemalite, nor is it soluble in acids. Stellite 
is fusible into a white enamel, and forms a jelly with muriatic acid. 
Composition. Magnesia 51.72, silica 12.57, peroxide of iron 5.87, water 29.67 ( Thom¬ 
son ). 
Geological Situation. Nemalite has heretofore been found only in thin veins in serpen¬ 
tine and greenstone. It was first noticed at Hoboken in New-Jersey, by Mr. Nuttall. 
LOCALITIES. 
Rockland County. This mineral is found in very thin veins in the greenstone at Piermont, 
where it exactly resembles the specimens found at Hoboken and Bergen hill. It is not com¬ 
mon at the former locality; and the stellite, which is more abundant, may easily be mistaken 
for it, as the fibres of that mineral are sometimes parallel. 
SERPENTINE. 
[From the resemblance which it sometimes bears to the skin of a serpent ] 
Serpentine. Cleaveland, Phillips, Bcudant and Shepard. — Precious Serpentine, or Hydrous Sesquisilicate of 
Magnesia. Thomson. — Prismatischer Serpentine-Steatit. Mohs. 
Fi §- 185 - Description. Colour various shades of green, particularly leek-green 
and mountain-green; also yellowish-grey and straw-yellow. It occurs 
regularly crystallized, also massive and disseminated. The primary 
form is said to be a right rectangular prism (Shepard). Fig. 185. The 
form of the crystals is generally so indistinct, that a few only of the faces 
can be traced. Texture compact, sometimes soft to the touch, tender but 
tenacious. Fracture conchoidal or splintery. Does not adhere to the 
tongue. Lustre resinous, inclining to pearly. Translucent, or translu¬ 
cent on the edges, to opaque. Hardness of precious serpentine, 3.5; of nephrite, 7.0. 
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