The Pioche weekly record. [volume] (Pioche, Nev.) 1877-1900, 1882-03-25
NEUTRALITY-SUSPICIOUS. VEINS.

At recent meeting Of the San Fran
cisco Academy of~Sciences. lrofessor
Joseph lie Conte of the University of
California read paper on the subject of
the formation of the Metalliferous
Veins, in which he gave the results
the Joint Investigations of Professor w
B. Rising and himself on the active for
nation of a metalliferous vein now in
progress in Lake county, All the ground
of the Sulphur Bank Quicksilver Com
pany. Professor LIE Conte said metallif-
crous veins were still forming there, as
they are also now at Steamboat Springs
in Nevada. He has watched the opening
of the Sulphur Bank Quicksilver mine
since 1877. He spoke of the Coast Range
as very complex in its formation, being
cretaceous and tertiary, and ascribing its
birth to the end of the miocene period,
1t differs widely from the Sierra Nevada
formation, which is a very simple one.
North of San Francisco the Coast Range
is composed of eruptive rocks. The
country rock is all everlaid with lava.
st. Helena and Uncle Sam, each 1000
feet high, were once volcanoes. At Clear
Lake volcanoes have flooded the surface
over strata of sandstone and shale. In
this region have been many hot springs,
of solfataras, emitting carbonate sulphur.
cts. The time of volcanic activity was
at the beginning of the pliocene and con-
tinued much later, perhaps through o
portion of the quarternary period. The
sulphur bank at the surface resembles
ashes, but lower down pure silica is
found. Sulphur first appears near the
surface, but docs not continue deeper
than few feet. Deeper the vein turns
to cinnabar, though blue clay is found
and much sulphuric acid. Silica, half
consolidated is found in cheesy condi-
tion streaked with cinnibar and iron pyr-
ties. The work of the miner is now in.
terfering with natures laboratory, for a
metalliferous vein is in process of dscom-
position in fssure between sandstone
and shale, whose strata stands nearly
erect. Carbonic acid bubbles up SO as
to frequently extinguish candles. A
paste of cinnabar, silica and iron pyrites
was found in all stages, sometimes gal
atinous, then chessy and quite solid
Some brought away in cheesy state soor
soldifed. These two different kinds o.
chemical action are taking place; thu
primary is a solfataric action coming W
through assures in the lava cap from be
low, and secondary action is working
from above. The deposit of sulphur il
superficial Water descends from above
bearing many things in solution. He sale
the original volcanic rock is changed b,
acid vapors, etc., into pure chalky silic
or quartz in pure plastic state, also int
chalcedonic state. The latter condition
is when it deposits from hot liquid
cooling rapidly. Under other condition
it forms in six-sided crystals when deep
er from the surface. EtE.f
The Bodie Free Press says: If Profes
sor LIE Conte should visit Mono count,
he would find at Bridgeport viens Q
metaliferous quartz forming, through til
action of hot springs, in the plainest an
most unmistakabie. manner. We conside
the Bridgeport Hot Springs one Of tn
greatest natural curiosities on the Pacifi
coast, and one of the most instructive
upon the subject Of the formation G
metalliferous veins. .,..a