Eureka weekly sentinel. [volume] (Eureka, Nev.) 1887-1902, 1897-09-11

ores. which we're more or less mixed with
limestone, that the lode had yielded above.
II is calculated that the subterrsnesn
disturbance which created the Ruby Hill
fault raised the footwsll side OF the Pros
pect Mountain limestone, through the Eu-
reka Con. mine, about 1400 feet.
PROSPECT oUSTA
Rises TO an elevation considerably higher
than that Of Ruby Hill. showing that 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 reaches
sn altitude Of only 1891 feet above sea
level. IL is here seen that the difference
in the elevation of the two points Is 2,313
feet.
The ~outcroppings Of the ore bodies Of
Ruby Hill we're larger than those of Pros
poet 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
SlOE mlute, hDOut lDOOO ltot DciOW VIC tOpOi
the main ore chute and a little over 500 feet
below the main tunnel level. The surface
Of Ruby Hill is relatively fat when COM
pared with that Of Prospect Mountain,
which lie doubtless due TO the greater ero-
sion OF the former, and il is therefore fair
to believe that the ~outcroppings Of the
Ruby Hill ore bodies were, at one time,
no greater than those Of the Diamond and
Excelsior mines at the present; and IL the
theory generally accepted here-that the
ore solutions were forced up by in6ltra-
ton and dynamic pressure from below-is
correct. that relating to the difference in
size Of the outcroppings of Ruby Hill and
Prospect Mountain is not without q 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 remunerative IL has
been demonstrates that the ore bodies still
continue going down in the caves, below
the deepest workings of the Diamond and
Excelsior mines. 1t is also shown that the
ore continues dipping below the deepest
excavation in the Eureka Con. mine and
there is reasonable probability that ore
bodies may be found below the deepest
workings OF either Of the Ruby Hill mines
as valuable as those which were excavsted
above. II Is 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 and the same that the dis
connection occurred through excessive ero-
sion above the Prospect Mountain quartz
lite. and tina, the difference in the extent Of
the respective outcroppings upon Ruby
Hill and Prospect Mountain is due to the
erosion. Undoubtedly the erosion occur
red subsequent to the uphesval and rela.
tive creation Of the Ruby Hill fault. There
can be bat little question as TO the import
ami bearing Of thefsult on the presentstruo-
sure Of Ruby Hill and Prospect Mountain
and the relation Of the ore bodies to each
other. The former has been manifested
through diligent investigation instigated
under national authority. and it is quite
probable that the ascending ore. bearing
solutions passed up through the great ifs
sure and, by means of infltration and per-
collation. through the seams in the country
rock. were conveyed to and deposited in
the chambers and other cavities In the
limerick which were created by the pre-.
Viously occurrluB suDteIraneous uisturO-
ances.
The elevation OF the main tunnel level
at the Diamond mine is 1000 feet above
sea level. while that OF the highest point on
Ruby Hill Is only 1900 feet or theresbout,
and the elevation Of the Ruby Hill CROP
pings ia 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
in quantity and quality with greater depth,
and the yield Of gold in proportion to the
silver Ia increasing. The Diamond and
Excelsior mines are making o better show.
ing than did the Richmond or Eureka
Con. at the relative points Of elevation.
and their present condition 10 On augury
that they will become as famous and equal.
ly as productive and lucrative a. were the
Eureka Con. and Richmond mines 10 their
palmiest days, but deep level mining 10
needed as much In the one az In the others.
*The distinguishing names Of the forma-
tions Of Eureka District are local and we're
first adopted BY Mr.. Arnold Hague. the
geolosist in the field OF this division Of the
U. 8. G.. Survey Of the Fortieth Parallel.