ais . =f 
ae (| pridg s ‘3 
Kae OF "Alger on Crystallized Goll fiom Califia - 103 
. 
. 
pendent on a greater intensity of molecnlar attraction in one 
tion, or axis, than another. It would seem in this case, as 
m 
crystalline face within the cavity of the larger one. This is 
Swering to the natural size of the crysta 
reat size of these crystals, and “ti fact that some of the 
, gene contained portions of oxyd of iron probably produced by 
_ the decomposition of pyrites, have led some to regard them as 
" Radoriorehe of sulphuret of iron. Iam not disposed to ascribe 
any such forced and unnatural origin to these beautiful produc- 
tions. I believe them to have been formed under the ordinary 
circumstances of crystallization, either in an open space, or while 
surrounded by a matrix so soft and accommodating, as to allow 
them full Pio ot to take the form it was intended they should 
take. Were the crystals cubes, there might be some reason for 
regarding them in the light of pseudomorphs of iron pyrites, be- 
cause this is the most common form of pyrites, and, moreover, all 
the pyrites that I have seen from California, has been in that 
form. But, we may well ask, who has ever seen even a cubic 
pseudomorph of gold? Crystals of gold are rare, cubes particu- 
larly so, and yet this form, on account of its simplicity, is made 
the primary form ; whereas it would seem as reasonable in cases 
of the regular system, to select that form as the primary which 
is most commonly and perfectly presented by the mineral, pro- 
vided there is no cleavage to guide us in the determination; and 
there does not appear to be any, well made out, among most 
of the native metals. By assuming those which most commonly 
occur in nature, we seem to recognize a sort of inherent disposi- 
tion, a preference, as it were, which is shown by the mineral it- 
self: and we avoid what seems to be a palpable inconsistency, 
Bet 
a ie 
* The two large crystals above described were obtained from the very choice and 
eertited collection of specimens, made with great care, and at no small expense, by 
Platt. This gen i 
hourly conta ns returning m the mines, has evinced his good taste by 
bee ben the bo eesti btained by them. He has erie 
finest amateur r collection hitherto brought from California t 
comprises great varie of ra 
here and and there ns by ig ‘all = er being sometimes most fantas- 
tically joined He informs me that in obtaining this 
collection, he b enced ed to am sidiieis oll wine than, Sour wnillicis'ot daltaee. 
4 bs ‘or it may be the result af that kind of erianiinnion which . 
beautifully shown in the third figure on ihe last page, also an- 5 
