Eureka weekly sentinel. [volume] (Eureka, Nev.) 1887-1902, 1897-10-16

ores, which we're more or less mixed with
limestone, that the lode had yielded above.
IL IL calculated that the subterrsnesn
disturbance which created the Ruby Hill
raised the fcotwsll side OF the Pros
pect Mountain limestone. through the Eu-
reka Con. mine, about 400 feet.
PROSPECT n
Rises to an elevation considerably higher
than that Of Ruby Hill, showing Ast the
erosion OF the latter locality must have
greatly exceeded that OF the former. Pros
pect Peak, the highest point on Prospect
Mountain, has an elevation Of 1904 feet,
and the highest point on Ruby Hill breaches
an altitude OF only 1891 feet above sea
level. Il lie here seen that the difference
in the elevation Of the two points Is 2,3l3
feet. a..
The ~outcroppings of the ore bodies OF
Ruby Hill were larger b those OF Pros
pect Mountain, but the difference may be
accounted for In the excessive erosion OF
Ruby Hill. In the main body of Prospect
Mountain the ore bodies generally augment
in size with the increase OF depth. The
deepest workings in Prospect Mountain,
following the ore downward from the sur
face, are found In the Diamond and Excel
sior mines, about /, 600 feet below the top OF
the main ore chute and q little over 500 feet
below the main tunnel level. The surface
Of Ruby Hill is relatively fiat when COM
pared with that of Prospect Mountain,
which is doubtless due to the greater ero-
sion Of the former, and 1t 10 therefore fair
70 believe that the outcroppings OF the
Ruby Hill ore bodies were, at n time,
no greater thar those Of the Diamond aud
Excelsior mines at the present; and II the
theory generally accepted here-that the
ore solutions were forced up by infltra-
ton and dynamic pressure from below-is
correct. that relating to the difference in
size OF the o~utoroppings OF Ruby Hill and
Prospect Mountain 10 not without o reas-
enable basis.
The question Of deeper exploration in
Ruby Hill and Prospect Mountain has re.
Gently been discussed here. and there has
been no reason sdduced TO show why the
work should not be remunerstive. IL has
been demonstrated that the ore bodies still
continue going down In the caves, below
the deepest workings Of the Diamond and
Excelsior mines. IL 10 also shown that the
ore continues dipping below the deepest
excavation in the Eureka Con. mine and
there 10 reasonable probability that ore
bodies may be found below the deepest
workings OF either Of the Ruby Hill mines
as valuable as those which we're excsvated
above. 1t Ia manifest that the limestone
bodies OF Ruby Hill and Prospect Noun
tain, at present separated by the granite
and Prospect Mountain quartzite. were
originally one aud the same; that the dis.
connection occurred through excessive ero-
sion above the Prospect Mountain quartz.
lite, and that the difference in the extent OF
the respective outcroppings upon Ruby
Hill and Prospect Mountain 10 due to the
erosion. Undoubtedly the erosion occur
red subsequent to the upheaval and rela-
tive creation OF the Ruby Hill fault. There
can be bat little question as TO the import
ant bearing Of thefault on the presentstruo-
lure OF Ruby Hill and Prospect Mountain
and the relation Of the ore bodies to each
other. The former has besn manifested
through diligent investigation instigssed
under national authority, and it is quite
probable that the ascending ore bearing
solutions passed up through the great fis-
collation. through the seams in the country
rock, were conveyed to and deposited In
the chambers and other cavities In the
llucIOCh 6utCA WoEp Okcote0 W VIZ fAo~
viously occurring subterraneous disturb
ances.
The elevation OF the main tunnel level
at the Diamond mine is 1900 feet above
sea level, while that OF the highest poipton
Ruby Hill 10 only 1900 feetor thereabout.
and the elevation Of the Ruby Hill CROP
pings is hardly more than 100 feet above
that OF the deepest workings Of the Dia-
mond and Excelsior mines. In the latter
the ore produced Is relatively improving
10 quantity and quality with greater depth,
and the yield Of gold in proportion TO the
silver 10 increasing. The Diamond and
Excelsior mines are making Q better show.
ing than did the Richmond or Eureka
Con. Of the relative points OF elevation,
and their present condition 10 an augury
that they will become % famous and equal.
ly ss productive and lucrative - we're The
Eureka Con. and Richmond mines In their
pslmiest days. but deep level mining 10
needed ~ much In the one 90 In the others.
*The distinguishing names Of the forns-
tions Of Eureka District are local and were
Hrst adopted BY Mr.. Arnold Hague. the
g~eologist In the Geld Of this division OF the
q. 8. g. Survey Of the Fortisth Parallel.