The Salt Lake herald. [volume] (Salt Lake City [Utah]) 1870-1909, 1908-12-27

seated intrusion: the trachyte mass, as
an intrusion near the surface il not
actually a flow. The rhyolite occurs
/ only in wide veins or bikes cutting
( across and along the contact of the
! granite and trachyte. The dolerite is
/ found only in tine western portion Of
| the district and is a more recent in
trusion than the rhyolite. 1t is closely
associated with the rhyolite and often
forms a second dixie in a rhyolite Ike
Relations of Faults and Dykes.
| Two series of faults are readily rec
ognized in the district. The one series
is of the same age as the rhyolite
bikes. the dixie of rhyolite merely rep
resenting the line of the fault or
parallel fault through the granite and
trachyte. So wide are these faults that
| they are really zones of brecciation.
In some cases they are found to be
from 200 to 300 feet wide. Seven large
and distinct faults were traced through
the district, while many more smaller
faults were observed paralleling these
for a short distance. These zones of
brecciation and the rhyolite bikes were
mineralized subsequent to the injec-
ton of the dolerite. The ore matter
consists of iron. copper. lead and zinc,
deposited being responsible for the
presence or absence in quantity of GER
tain ores. Thus in the Cactus mine
copper and iron are the two more prev
alent metals, the ore being deposited
i'm a granite, rhyolite and dolerite
mass; while in the limestone of the
Horn Silver, and the Washington, lead
and zinc ores are the more important
products, though copper is also pro-
duced in commercial quantities.
The relation between the rhyolite
bikes and the red zones of brecciation
is marked and distinct. Nearly all of
the ryholite bikes We're found to run
into each other, while two of the most
prominent red zones of brecciation and
one rhyolite dixie were found to center
at the Horn Silver mine, which in ad-
dition 10 being thus favored as CEN
ter of faulting, also has a trachyte lime
contact passing through il. Because of
this centering of faults and dikes, con-
dltions We're most favorable for the dis
position of ore. And conversely since
so many fault lines and bikes centered
at the Horn Silver il has been not at ali
unnatural for more than one party to
insist that he had the Horn Silver vein.
Touching the Ore Zones.
Following outward and westward on
the two red zones of brecciation is the
King David property. located entirely
on sedimentary formation. On one OF
these zones a little more to the west
is the Block property. while on the other
are the old Washington and Iron Devil
mines. now being developed by the Cup
ric Mining and Development company
To the north on the rhyolite dixie.
which is recognized as passing through
the Horn Silver, though not actually
exposed on the surface, is the Frisco
Contact property.
Just as the Horn Silver property has
been the center of extra faulting and
breaking in the sedimentary rocks. thus
cavities where the ore might be
deposited. so the Cactus and adjoining
in Copper guIch have been
the center of similar faulting in the
igneous rocks. The properties on this
favored zone in Copper gulch are the
Cactus, the Blackbird and the Comet
The two big glory holes of the Cactus
property. whose diameters are 100 and
800 feet. are for the most part In this
brecciated and mineralized material.
The Comet property has but one claim
partly on this material.
Undoubtedly the liberalization of
these two centers. the one in the sedi-
mentary rock and the other in the ig-
neous rocks occurred at the same time. |
In both. however, there has been a Sec
ond naturalization. giving rise to the
high grade ore bodies. which show up
particularly strong in contrast with the
low grade in the Cactus property II
was because of the finding of such q
body of later naturalization that the
So dividend of 1907 and the only one paid
by the Newhouse property was made
possible.
The Imperial property. owned by the
Nevada-Utah Mining company. is To-
Gated on fissure of the same origin a.
those of the Horn Silver and the rhyo-
lite dikes of the Cactus. This fissure
was not connected up with the series
but there is ample evidence of
its being of the same series It is con-
fined on the surface almost entirely to