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An Account of some New and Extraordinary Minerals. 243 
allel with the crystals of spinelle, often greenish and compact, 
at other times tinged yellow by an admixture of brucite. - 
‘hese crystals bear not the smallest resemblance to the 
marmolite of Nuttall, erroneously referred to serpentine, on 
the mere ground of chemical affinity, by Mr. Vanuxem, 
he same mass also are associated very large prismatic 
crystals of chromate of tron, at least so they appear to be, by 
the beautiful green colour which they impart to nitrate of pot- 
ash, having a specific gravity of 4.30. Some of these prisms 
are an inch in breadth and two inches in length, with two late- 
ral pees: broader than the rest. 
ding matrix of the whole is, as usual, crystalline 
a rhanads of lime, with mica and some appearances of hema- 
ttic iron. A few greenish spinelles occurred near the same 
place, and the neighbourhood abounds with small black and 
blackish gray spinedles. Not far from the same locality also _ 
is , associated generally with a fine green and crystal- 
line serpentine, the re spinelle of various shades and degrees 
of translucence ; when dark it passes into reddish brown, 
but when smaller and more bright, it approaches to rose red. 
These are from a line in diameter to three quarters of an inch 
on. each side of the bases; now and then they occur, in he- 
mitrope—but are seldom or: never emarginated, Jike the green 
ceylanite of Franklin 
At Byram also, a few miles from Sparta, the red spinelle 
has been found, by William Ingliss, Esq. Some of these, ap- 
proaching toa chocolate brown in colour, give a base of one 
inch and a quarter on each plane. At the same place we 
have also found the green coylnpte though much inferior in 
colour and translucence to that at Franklin. 
The magnitude of other rei at this place (Warwick) 
is equally surprising as that of the spinelles. Crystals o 
scapolite, terminated, are to-be found, each of the six Sal 
of the prisms measuring four inches—or a circumference o 
twenty-four inches, or even more. They are of course rough 
and corroded ; but the smaller prisms, often with narrow re- 
po ein on the edges, are very perfect and almost trans- 
parent—all of these slightly tinged with green. 
f the amphibole genus we meet with several varieties 
finely crystallized, tle black with six-sided prisms, each face 
sometimes is an inch in breadth. Actynolite in short and con- 
fused prisms, and a chocolate-brown finely crystallized variety, 
both in large and smal) crystals, of the usual form, and alsp 
