Eureka weekly sentinel. [volume] (Eureka, Nev.) 1887-1902, 1897-07-10

quivocally declared that the ore "a there,
and more than that, they believe that u
goes down deeper and in paying guam
titles.
Mr.. Clarence King. the eminent geolo-
gist Of national fame. who formerly had
charge Of the Richmond mine, and is quite
familiar with the physical condition OF
Ruby Hill and the manner Of the deposit
tion Of the ore bodies, has expressed the
opinion in the most indubitable manner,
that exploration should be carried TO fur.
ther depth of 900 feet or theresbout, and
that there ia no geological reason why ore
should not be found in as valuable guam
titles as il was found above. il the work
were done. He thought that gold. bearing
arsenicsl pyrites and silver bearing
gslena would be found in more compact
form, and hence rioher than the oxidized
ores, which we're more or less mixed with
limestone, that the lode had yielded above.
IL Ia calculated that the subterranean
disturbance which created the Ruby Hill
fault raised the footwsll side OF the Pros
pect Mountain. limestone, through the Eu-
reks Con. mine, about 1400 feet.
PROSPECT MOUNTAIN
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 Q. GOA feet,
and the highest point on Ruby Hill breaches
an altitude Of only 1921 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 were larger than 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 900 feet below the top of
the main ore chute and 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 doubles, due TO the greater ero-
sion OF the former, and il is therefore fair
20 believe that the outcroppings OF the
Ruby Hill ore bodies were, at one time,
no greater than those OF the Diamond and
Excelsior mines a. the present; and II the
theory generally accepted here-that the
ore solutions were forced up by in6ltra
tion 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 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 adduced to show why the
work should not be remunerstive. 1t has
been demonstrated 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 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 were excavated
above. 1t 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-
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 upheaval and rels-
tive creation OF the Ruby Hill fault. There
can be bat little question as to the import
ant bearing OF thefau on the present struc-
ture of Rnby 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 1t is quite
probable that the ascending ore bearing
solutions passed up through the great fis-
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 were created by the pre-
viously occurring subterrsneous disturb.
ances.
The elevation OF the main tunnel level
Of the Diamond mine is 1900 feet above
sea level, while that OF the highest point on
Ruby Hill is only 1900 feet or Whereabouts.
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
in quantity and quality with greater depth,
and the yield OF gold in proportion to the
silver is increasing. The Diamond and
Excelsior mines are making better show
ing than did the Richmond or Eureka
Con. at the relative points OF elevation,
and their present condition ia an augury
that they will become as famous and equal.
ly as productive and lucrative as were the
Eureka Con. aud Richmond mines in their
palmiest days. but deep level mining is
needed as much in the one as In the others.
*The distinguishing names OF the forma'
tions Of Eureka District are local and we're
frat adopted by Mr.. Arnold Hague. the
eeoloeist in the field OF this division Of the
U. s. G. Survey Of the Fortieth Parallel.
Two Armtes-the Regular and 1r.
regular