Eureka weekly sentinel. [volume] (Eureka, Nev.) 1887-1902, 1897-11-20

ores. which were more or less mixed with
limestone, that the lode had yielded above.
Il. il calculated that she subterrsnesn
disturbance which created ihe Ruby Hill
fault raised the footvall side Of the Pros
pee, Mountain limestone. through the Eu-
reka Con. mine, about 400 feet.
PROSPECT MoUNIAIS
Rises to sn 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
an altitude OF only 1921 feet above sea
level. Is is here seen that the difference
in the elevation Of the two points is ASS
feet.
The ~outcroppings Of the ore bodies OF
Ruby Hill we're larger than those Of Pros
pee. 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 /, 900 feet below the top OF
the main ore chute and a little over 500 feet
below the main tunnel level. The surface
VI Ruby Hill is relatively fiat when COM
pared with that Of Prospect Mountain,
which is doubtless due to she greater ero-
sion OF the former, and il ia therefore fair
TO believe that the outcroppings q the
Ruby Hill ore bodies we're, st one time,
no greater than those OF the Diamond and
Excelsior mines st the present; and II the
theory generally accepted here-thst the
ore solutions were forced up by infltrs-
ton and dynamic pressure from below-is
correct. that relating TO the difference in
size Of the o~uteroppings Of Ruby Hill and
Prospect Mountain Is not without q ress-
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 adduced 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. II is also shown tina, 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 TIE deepest
workings Of either Of the Ruby Hill mines
as valuable as those which we're exeayated
above. 1t Is manifest that the limestone
bodies Of Ruby Hill and Prospect Noun
tain, at present. separated by the granite
and Prospect Mountain quartziie, were
originally one and the came that the dis
connection occurred through excessive ero-
| sion above the Prospects Mountain quartz
| lite, and that 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 10 the import
ant bearing Of thefsulto on the presentstruc-
ture OF Ruby Hill and Prospect Mountain
| and the relation OF the ore bodies 10 each
other. The former has been manifested
through diligent investigation instigated
under national authority, and il 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. we're conveyed to and deposited in
the chambers and other cavities in the
limerick which we're created by the pre-
viously occurring subterraneous disturb-
ances.
Tno elevation OF the main tunnel level
at the Diamond mine is 1900 feet above
sea level. while that Of the highest point on
Ruby Hill IL only 1900 feet or thereaboui,
and the elevation OF the Ruby Hill crop.
pings Is hardly more than 100 feet above
that Of the deepest workings Of the Dis-
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 IL increasing. The Diamond and
Excelsior mines are making q better show.
ing than did the Richmond or Eureka
Con. at she relative points OF elevation,
and their present condition Ia An augury
that they will become 90 famous and equal
ly as productive and lucrative a. were the
Eureka Con. add Richmond mines In their
palmiest days. but deep level mining Is
needed As much 10 the one as In the Others.
(*The distinguishing names OF the forma-
sions Of Eureka District are local and were
irss adopted BY Mr.. Arnold Hague. the
RsoloQist 10 the field Of this division Of the
q. 8. G.. Survey OF the Fortieth Parallel.