Eureka weekly sentinel. [volume] (Eureka, Nev.) 1887-1902, 1897-08-28

ores. which we're more or less mixed with
limestone, that the lode had yielded above.
II, IL calculated that the subterranesn
disturbance which treated the Ruby Hill
f.ult raised the footwail side OF the Pros
pect Mountain limestone. through the Eu-
reka Con. mine, about l400 feet.
PROSPECT n
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
nee, 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. II is here seen that she difference
in the elevation Of the two points Is 2,313
feet. J..
The o~utcroppings OF the ore bodies Of
Ruby Hill were 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
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 fat when conn
pared with that Of Prospect Mountain,
which is doubtless due to she greater ero-
sion Of the former, and ii is therefore fair
TO believe that the outcroppings OF the
Ruby Hill ore bodies were, st n time.
no greater han those Of the Diamond and
Excelsior mines st the present; and II the
theory generally accepted here-that the
ore solutions were forced up by indltrs-
ton and dynamic pressure from below-is
correct. that relsting to the difference in
size Of the o~utcroppings Of Ruby Hill and
Prospect Mountain is not without . ress-
enable basis.
The question o. deeper exploration In
Ruby Hill and Prospect Mountain has re-
Gently been discussed here, and there has
been no reason sddueed 20 show why the
work should not be remunerative IL has
been demonstrated thai the ore bodies still
continue going down in the caves, below
the deepest workings Of the Diamond and
Excelsior mines. II ia 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 excsvated
above. 1. ia manifest that the limestone
bodies OF Ruby Hill and Prospect Noun
tain. at present separated by the granite
and Prospects Mountain quartzite, were
originally one and 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 o~utcroppings upon Ruby
Hill and Prospect Mountain Ii due to the
| erosion. Undoubtedly the erosion occur
red subsequent TO the uphesval and rels-
tive creation of the Ruby Hill fault. There
can be bat little question as 10 the import
an. bearing OF the fault on the presentstruc-
ture of Ruby Hill and Prospect Mountain
and the relation OF the ore bodies to each
| other. The former has bssn manifested
through diligent investigation instigated
under national authority, and ii is quite
probable hat 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 were created by the pre-.
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 point on
Ruby Hill il only 1900 feet or Whereabouts,
and the elevation Of the Ruby Hill crop
pings IL 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 q better show
ing than did the Richmond or Eureka
Con. 1t the relative points OF elevation,
and their present condition 10 an augury
that they will become as famous and equal
" as productive and lucrative ~ were tbs
Eureka Con. and Richmond mines In theiI
pslniest days. but deep level mining Ii
needed as much In the one 90 In the Others,
t*The distinguishing names Of the forms
tions OF Eureka District are local and wert
frat adopted by Mr.. Arnold Hague. ths
g~eologist In the field OF this division Of th.
II. q. G.. Survey OF the Fortieth Parallel.