Crystalized Steatite. 275 
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are three-eights of an inch in diameter and more than half 
an inch in length. Ihave one which is double the dimen- 
sions just mentioned. ‘The surface of the crystals is of a 
brown colour, produced by the action of the weather. But 
when the crystals are separated, their faces are of a yellow- 
ish white colour. When fractured, the crystals present an 
uneven surface, with a structure inclining to the fibrous. 
The same fibrous appearance is seen on some parts of the 
Stéatite which is destitute of crystals. The crystalline 
‘structure is exceedingly indistinct, except near the sur- 
face. 
The predominant form of the crystals is a six-sided prism, 
terminated at one or both extremities by a pyramid of the 
same number of sides. The truncations are numerous,— 
sometimes on the edges of the prism or pyramids, and at 
others on the angles, or at the vertex of the pyramid, form- 
ing very different faces. In one case, the face produced by 
truncation is of the kind, which the Abbe Hai designates 
by the term, Rhombifére. These crystals agree generally 
with the description of the prismatic crystals of Steatite, 
found in the Principality of Bareuth. “ Mineralogists are 
not agreed respecting these crystals, some considering them 
as true crystals, others as false ones.” Jameson considers 
them decidedly pseudo-morphous, the prismatic crystals hav- 
ing been formed in moulds made by crystals of quartz. See 
Rees’ Cyc. The erystals found in Middlefield very much 
resemble some rock-crystals. But when this group of crys- 
tals is examined, there seem to be insuperable objections to 
the hypothesis, that they are pseudo-morphous. No mould, 
formed by imbedded crystals which had fallen out, could 
approximate so nearly to the form required for the produc- 
tion of the group under consideration, The crystals, too, 
sometimes separate from each other, and the contiguous fa- 
ces are perfectly smooth and regular, neither of which fa- 
ces could have been formed by a mould, for no part of the 
mould could have intervened without remaining between 
them. But no trace of the substance of the mould is to be 
seen. The supposition that they were first formed in 
moulds, and afterwards fell into their present situation, is to- 
tally absurd, and, when this group is considered, is ridicu- 
lous. The crystallization appears more perfect near the sur- 
face of the crystals, and the imperfect crystallization extends 
