Tonopah bonanza. [volume] (Butler City [i.e. Butler], Nev.) 1901-1909, 1904-12-31

known to Mr.. Spur two years ago.
have shown a moderate amount Of
gold and no silver.
All Indication show that this sllici-
hcation land the accompanying min
~erailzation) is the work Of hot springs,
and that these irregular reefs repre-.
sent the horizontal sections of columns
OF rocks traversed by rising columns
OF hot water. Had the rocks been
strongly fractured we should have
had veins, like those of the early an.
deslte at Tonopah, which are also
probably due to hot spring action:
but at Goldfield the lack of such a
fracture system resulted in this curl.
Gus and rather unusual type of de-
posit. 1t follows that the quartz
reefs will probably as a rule extend
deeper vertically than ECONOMICALLY.
and so have roughly the nature OF
columns or pipes.
The ores are often of very HIGH
grade. As an extreme example may
be noted a shipment of fourteen and
a quarter tons from the Sandstone
(Kendall claim, which when worked
in a stamp mill yielded $45, 1873 net,
while the tailings still contained
$1,000 to the ton. From the Nc
Kane Bowes lease on the Jumbo.
5000, 900 was taken out in five months.
from a space of one hundred feet
horizontally and two hundred feet
vertically Oh the shoot. One small
shipment Of 917 pounds of ore from
TINS lease gave gross returns of
VA, 7o6. The whole production of
the camp has been from ore which
may be roughly estimated as aver
aging two hundred dollars to three
hundred dollars per ton. or more.
The values are all in gold; silver is
usually practically absent, although
the shipping ore from the Combin.
alton mine contains from one to
three ounces.
Most of the rich ore which up to
the present time has been extracted.
has been oXidized ore. The ores are
mixed sulphides Casually pyrite) and
oxides, clear up to the surface. The
oxldized material, which follows
cracks and seams, is usually several
times, sometimes several hundred
times, as rich as the unoxidized
portion, The irregular spongy ma
ture of the free gold particles ii such
oXidized material completes the
proof that this gold has been dis
solved and redeposited in a concen
trated form during the process of
oxidation Iron sulphate derived
from oxidation Of the pyrites is the
probable agent.
Concerning the origin of these
sulphides, it is probable that some. so
far as can now be seen, are purely
primary, while others have been
formed subsequently to the main
sillcitication Of the reef. as in the
Combination mine. Here the rich
auriferous sulphides have formed in d
broken one tbreccia zone) IN the sill.
ieiiied barren roof, and occur as
seams. aud often as coating on the
pebbles in the breccia. The presence
OF elements like arsenic, anthony
and tellurium in the subsequent sui
phlde ore suggests a deep seated
origin.
Beside the elements mentioned
above, bismuth occurs in the January
in the oxidized pres in the form of
silvery scales, which is, as deter
mined by Dr., Hillebrand, the oxide
bismuth. In the Combination long
needle like crystals have been found.
which according to the manager, Mr..
Collins, gives the chemical test for
bismuth sulphide, bismuthinite. The
silvery mineral above noted is m
times found, in the January, ar.
ranged in long rod like forms, and
these are probably pseudomorphs
after the sulphide In the January
this silvery mineral is usually, but
not always, an indication of rich ore.
Barite is a common mineral in all
these deposits, but is not abundant.
The indications are, therefore, not
unfavorable to the continuance of
high grade, or at least good grade
ores, down to considerable depths.
The o~re-shoots, however, are curry
ing, irregular and often lenticular,
but 1t may happen that below a shoot
which has come to an end, another
shoot may be found occupying a
slightly different relative position, or
even overlapping the first. Similar
~, the main quartz masses as a whole
can be expected to show little repu.
Ia ritV II Jeptb. tboy ,o -