Mohave County miner., 1893-09-30
The Origin Of Gold.

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the manner 10 which the matter has
reached its present position, is one
which has at all times excited consider.
able attention, and the number OF
theories put forward has been almost as
great as the number OF writers on the
subject, writes Philip Lake, OF Cambridge
England, in Science.
IT is easy 10 understand the presence OF
In Alluvial deposits. for this has clearly
been derived from pre-existing rocks;
but the difficulty lies in determining hox
the auriierous quArrz-reefs aud other
rocks which We look upon AS the home OF
the gold, became impregnaied. M
Sir Roderc Murchison, from his obser-
vations in the Ural mountains. originally
held that non-alluvial gold was only
found in PAleozoic rocks, and principally
in his Lower Siurian, but he believed
that II was not introduced into these
rocks until shortly before the Drift period.
Subsequently he was led to modify these
views 10 certain extent, and to admit
that Secondary and Tertiary st:ata when
penetrated by Igneous rocks or lmpreg-
mated by mineral veins, might also con-
tain gold.
More recent observations show that
gold may be found in rocks Of any aye
in meramorphic strata; but all the ev,-
dence seems to support Murchison's
next contention, viz, that gold i, OF ig-
neous origin.
There is probably no more instructive
area to illustrate this than southern
India, where the distribution Of gold has
been carefully worked out by MIR. X. b.
Fo,ae, OF the Geological Society of India.
Almost the whole Of this part Of India is
made OF crystalline and metsmorphic
rocks; and IN il there are large number
OF gold mines, more or less rich. A
closer examination OF the country shows
that We have here large mass Of gneissic
and yraniioid rock which is crossed by
number Of bands of schist, lava flows,
hematite beds and conglomerates. Mr.
Foote has shown that these bands belong
to a system which is distinct from, aud
newer than, the gneiss, and to this
sy stem he has gwen the name OF Dhar-
war. He has also shown that all the
gold fields OF southern India, with the
possible exception OF the WyDaad, he
within these Dharwar hands.
As usual, the gold Is found principally
in quartz reefs; and il is remarkable
fact that though qnariz.reefs are by no
means uncommon in the gneiss, AS we'll
as in the Dharwas beds, yet those in the
gneiss are never aurie ons. IL is clear.
therefore, that the gold cannot have been
introduced Into the reefs from below, for
in thar case there would be no difference
in that respect between the reefs in the
Dbarwar.
Only one other possible conclusion re.
mains, viz, that the gold originally lay
Ia the Dharwar rocks themselves. and
that it has since, by some process OF se-
gregs'ion, been gathered together in the
quartz reefs.
II has already been stated that lava
flows occur among the Dharwar rocks:
and my own observations have led me
to believe that msny Of the schsts also
are lavafows. In fact a very large part,
il not the greater part Of the system, ap-
pears TO be Of volcanic origin.
II may be concluded, therefore, that
the gold which We now find in the auri.
ferons reefs OF southern India wa, derived
from the rocks Of the Dharwar system; |;
and that it was Originally brought up
from the depths Of the earth by the lava
flows which form so large part Of that
system.