Eureka weekly sentinel. [volume] (Eureka, Nev.) 1887-1902, 1897-08-21

b.rs mines, and Through :ke Uncle sam
and Hamburg mines farther TO the south
wArd. 1t faults all formstions, but Is it,
SELF nowhere ssulted or dislocased so far as
can be determined. 1t has been traced
mon the surface and is identified under
ground BY its filings Of rhyolite. ore,
ledge material and composite OF rhyolite
and clay, the latter having been produced
by sttrition where the walls are close To-
getber or nearly so. IL has q most import
ant bearing On the present structure OF
Ruby Hill and the country 10 the south
ward, IS also on the relation OF tue
ore bodies 20 each other. Throughout its
entire course ii lie found to be the key TO
the structural problem OF the Ruby Hill
and Prospee, Mountain miners,izsd zones.
The country southwest, on the tootwall
side of the fault, has been raised several
hundred feet relatively 10 the hanging
wall. 1t is probable that there was up
heavsl aud subsidence. but that the latter
exceeded the former. Taken in connection
with all Of the mines to the southeast, ii Is
found to be a fault plane along which the
whole southwestern country has been
raised from 500 to 1000 feet. There can
be no question that the key 10 the problem
OF deep mining In Ruby Hill and Pros
pect Mountain will eventually be found in
the Buby Hill fault.
The limestone Of RUBY Hill is divided
into two sections, which we will designate
The "~front'' and black" limestone. The
latter forms a wedge which, taken through
the Eureka Con. nins, extends from the
surface downward to near the 18th level
end lies between the qusrtzite, the face OF
which has q mean dip Of about 40 degrees
and the fault fissure, which dips at an an
gle Of about 70 degrees. This. which We
shall call the upper wedge, lies on the
southwest or ~footwsil side OF the assure
and has been raised in this locality about
1,40O feet relatively above the lower wedge
aud narrows 10 q hin edge 81 its "
extremity. Il il remarkable for lts crushed
and broken condition. II was 10 this
wedge that sill OF tie tremendous ore bod
les which made Ruby Hill fsmols IN the
early days OF the district were mined.
The exploration Of the front limestone,
which o~verlies the fault to the southwest,
has not been sufficient to determine
whether either largo deposits or any ore at
all may be found in it. From the narrow
par. OF the upper wedge, downward, as
seen upon the 18th and l4th levels. "a we'll
as upon the l,200-foot crossut from the
LOGAN shaft, below the 14th level OF the
Eureka Con. mine, the face OF the quartz
tie forms the fooiwsll OF the fault, the lat
ter msintainins tie dip at an angle OF 10
degrees, the same "a 1t does above. Below
the 18Th level, with its thiDest edge upper
most and its form inverted, as compared
with the upper wedge, but situated upon
the northeast OF hanging wall eide OF the
fault IL o
LOWER WEDGE OF LIMESTONE
Identical in character with the upper
wedge. This is crushed and shattered in
precisely the some msnne and. Fubse-
quent to the upheaval and subsidenoe
along the fault line, was doubtless an IN.
divided par. of the block OF limestone
which forms the upper wedge.
The future OF Eureka District will de-
pend largely on deep level mining; not
that the levels near the surface ere ex-
hausted Of ore, for on the contrary, there
are hundreds of the smaller mines and
prospects Of the district capable OF pro-
ducing the precious metals that are seldom
or never talked about; but there is no
question of doubt among the experienced
miners who have worked on the deepest
levels OF Ruby Hill shat there are bodies
of ore to be found in the lower wedge OF
limestone as valuable az those which
were excavsted in the big chambers OF the
upper wedge. :.
The exploration OF the lower wedge would
require the expenditure of large sums OF
money. no d~oubs-perhaps hundreds OF
thousands, possibly millions Of dollarsi
bot when it is remembered that the Eu-
reka Con. and Richmond mines have alone
paid over ten million dollars in dividends
- -raAn --nHar ~ nannfa Uaotfhu
and when ii is further borne in mind that
the ore Is known to enter the lower wedge
Of limestone and to go down below any
depth yet attained In Ruby Hill. IL 10 not
unreasonable TO believe that deeper ex-
ploration in the lower wedge would pay.
The only reason given 10 the public by
the Eureka Consolidated management for
not sinking the LOGAN shaft deeper and
erosscntting TO the lode below the LOGAN
1200-fcot level. was that the machinery
upon the LOGAN shaft was inadequate for
the dual requirements OF draining the mine
Of water and raising the material broken
underground to the surface; they were I'M
willing 10 continue draining the hill OF
water unless one or more OF the companies
that we're operating in Ruby Hill would
divide the burden OF expense with them.
Il Is q settled fact that the machinery was
defective for the general requirements OF
the mine, but the volume Of water to be
contended with and all Of the material that
could have been broken in the mine could
have been raised to the surface with ma
chinery that should not have cost over
one-ifth OF the sums that were paid for
the cumbersome plant which now stands
idle at the LOGAN shaft. 1t ia probable
that
THE TRUE WATER LEVEL
OF the Ruby Hill lode. if there is such .
thing, has not yet been encountered. This
is q moot question. The principal flow OF
water that was encountered in the 1900
foot cresscut from the LOGAN shaft came
from the quartzite. which was uselessly
penetrated, but II proper measures were
taken, that flow could be easily stopped.
The balance Of the water came from the
shale in the main hanging wall of the lode,
az well as from seepage from the surface,
but was immaterial. The limestone itself
is comparatively dry, which fact has been
amply proved upon the lowest workings OF
the Richmond mine, which are deeper than
the bottom Of the LOGAN shaft. Before
the qusrtZite was broken into in the LOGAN
crosscut, when the water came
in in ils greatest volume. fully seven feet
In width Of ledge material was encountered
between q wall OF intercalsted shsle and
quArtzite. In direct connection with the