a 
‘ ¥ ee t 
: ie ee to ih, 
eae ony 4 
. 80 _ Hf. Wurtz on a supposed New Mineral. fe “og 
acids. Dr. Chilton had observed carbonate of Bébinuth with thie: * 
- Quarry,” the well-known locality of prehnite. It occurs as an 
gold rock of South Carolina, some time before I found this, and’ 
sent me a specimen of itv This o e, (bismutite,) from the gold 
district of Chesterfield, S. C., has ‘ben analyzed by Rammell a 
berg, (Pogg. Ann. , Ixxvi, 569, 1849, ) who obtained Bi90-00, 6658... . 
3-44, whence he tias deduced the formula 3(Bi 6+)+Bi 4, — x = 
alent to 4Bi, 3G, 4H. es 
Arr. XIJ.—On a supposed New he Be eel by Henry 
urTz, of New Yor 
Tis mineral was found near Cambridge, Mass., at “ Milk Row 
incrustation upon the surface of the syenitic rock, coating the 
sides of fissures, and presenting the appearance of brilliant plates 
pie one another like the scales of a fish. 
Its color is black; lustre, resinous; streak, dark olive green; 
jeertae alistinetiy fibrous, somewhat like that of tremolite ; feel, 
soapy. Har dness, about 2; slightly translucent in thin laminees 
The fibres are brittle. No cleavage was found. Under the lens 
it exhibits white crystalline specks, which the analysis proved 
to be calcareous spar. 
It is easily decomposed with effervescence by hydrochloric = 
which is thereby colored deep green, silica being left behind a 
white powdef. Its fusibility is Secs that of natrolite, or 2 fe 
Kobell’s scale. he fuses to a dull black opaque globule which is 
slightly magne 
Two aelerevaane of the specific gravity, made upon two 
different specimens, gave the same number, 2°69, which being 
about the specific gravity of calcareous spar, no correction due to 
the 12 e v ~ cent. of this mineral which the analyses indicate, 
need be 
Guslitesive analysis indicated the presence of carbonic acid, 
water, lime, soda, silica, oxyd of iron and alumina 
For the quantitative analysis, a portion of the mineral was finely 
elutriated, and then dried at 212° in a steam-bath until it lost no — 
more weight. Attempts to separate the cale spar by means of 
very dilute acetic acid were unsuccessful. The _— became im- 
mediately colored red by dissolving some of the 
When the dark-green powder of this pach oar is fanned to red- 
ness in the air, it assumes upon cooling a red color, indicating 
peroxydation of the iron. The water desartninations were there- 
fore made in small bent tubes, which were sealed up immediately 
after the expulsion of the water, and the mass thus an rg out of 
contact with the air. The eaiines after the expulsion of the HO, 
had, in this case, a black color 
