Wo. 50.] 
Ill 
important characters with that described by Dr. Thomson in the fissures 
of the greenstone at Bergen-Hill, New-Jersey, and at Tappan Slote, 
Rockland county. Our mineral, however, as we shall presently see, 
diifers somewhat in its chemical composition. The following is the de- 
scription : 
Colour, snow-white. It consists of a congeries of crystals radiating 
from various centres, which run into each other in a confused manner. 
When these bundles are broken up, they separate into needle-form crys- 
tals, which are exceedingly sharp. These needles are tough, and when 
subjected to the pestle appear like amianthus. Their shape cannot be 
determined, but they appear to be four sided prisms. Lustre, silky, 
shining. Translucent. Hardness, about 3.0. Specific gravity of a 
very closely aggregated specimen, 2.836. 
Before the blow-pipe, our mineral fuses readily, even when in quite 
large fragments, and with slight bubbling into a beautiful white enamel. 
With borax it melts into a transparent glass. It gelatinizes with muri- 
atic acid. When heated to redness in a crucible, it is partially fused. 
The following is its composition in 100 grains, according to my analy- 
sis, viz. 
Silica, - 54.60 
Lime, 33.65 
Magnesia, 6.80 
Oxide of iron, with a little alumina, 0.50 
Water and carbonic acid, 3. 20 
Our mineral differs from the stellite of Dr. Thomson, in its containing 
less alumina, oxide of iron and water. But these may after all be acci- 
dental ingredients. It must be confessed, however, that both of them 
bear a close resemblance in their characters to Wollastonite, except that 
the latter contains soda as one of its constituents, though in small quan- 
tity. But from all my experiments upon this mineral, I am inclined to 
believe that it belongs to the family of zeolites ; and if so, the only one 
with which it agrees is that above mentioned. 
Mr. Dana in his Mineralogy remarks, that the stellite of Dr. Thom- 
son is closely allied to the natrolite ; but the small proportion of alumi- 
na which it contains, and perhaps its entire absence in pure specimens, 
must keep it totally distinct from that, and indeed from all other mine- 
rals of the zeolite family. 
