The Anaconda standard. [volume] (Anaconda, Mont.) 1889-1970, 1898-07-18

quantities that II IL not determined in
Commercial assays. In the mines along
the east bank of upper Missoula gulch
II has proved an important part OF the
value. and IL was probably from these
veins hat the gold In the placer de-
posits was mainly derived. since both
silver and copper have been found IN
the placers. Manganese is
widespread in the silver veins and
wanting In all the copper veins. except
those that form a transition phase be
tween copper and silver veins.
Zinc is also very widespread. and in
greater AMOUNT in the silver than In the
copper ores. Lead Is IN fela
lively small amount.
Ore deposition in this region has
taken place through the agency OF
aqueous solutions. evidently alkaline IN
their nature. which probably gathered
into this particular place because it's
intensely assured condition rendered 1t
peculiarly easy OF access to circulating
waters. AZ TO the source from which
the metallic minerals were derived. no
direct evidence has been obtained, but
as the granite at present forming the
surface generally contains small
moun of the metals. II may be in
ferred that somewhere in depth within
reach OF the circulating waters there
were parts Of the great granite mass
sufficiently rich in the metals to have
furnished the deposits now found near
er the surface. The original mineral
bearing solutions evidently assembled
along the fissure planes and were prob
ably at high temperature. though not
necessarily under great pressure"
Later I'm the work the authors de-
scribe the lodes individually.
TT was upon the Parrot lode that the
first discoveries and earliest develop
ments OF copper ore were made. 1t has
now been traced almost continuously
from Missoula eulch to Silver Bow
creek. a distance of over two miles. and
in the greater part of this length has
been actually developed by under
ground workings. 1t has been
most extensively developed in the Gag
non-OriginHl ground, where the asso-
citation Of minerals in its vein materials
is unusual and varied. The
Anaconda lode has been traced through
the Never Sweat. Anaconda, st. Law
renee. Mountain View n Rarus lodes.
a length of o a mile. There is a
break In the underground workings east
OF the st. Lawrence ground, beyond
which there is a change in strike.
This is the most important ore
producer OF the Rarus and of the Ana
conda company's mines. Through this
latter the lode consists of one broad
vein or ore-bearins zone with minor
small parallel veins. which sometimes
JchiA Nhit o. VIII q obt NiN Afts
constituting a sort of spur vein.
The width of the lode varies. At
the west end. where IL consists of a
number of parallel veins, II rarely ex-
ceeds Is feet in width. and the spur
veins are about five feet wide. In the
Anaconda ground the main vein agere-
gates % to 40 feet in width. decreas-
ing to five feet in the east end of the
st. Lawrence. In the eastern
part OF the Mountain View ground the
lode consists of a single vein known as
the Johnstown. which is five to eight
feet wide. In the Rarus ground IL con-
sists of three distinct veins. with
quartz-porphyry on the footwall of the
northernmost. Two cross-faults displace
the veins. and between them the ground
is much broken and i"mpregnated with
ore. so that in places a width OF 100 feet
has been mined. The veins opened I'm
the ~Snohomish ground are supposed to
be n the extension of this lode; a 40
foot dixie OF duartz-porphyry is cut i'm
the workings"
The text also describes the Mountain
View-Colusa lode. the Moonlight, the
Ground Squirrel. the Syndicate. the
Bell-Modoc lode. the intermediate zone
and the silver lodes.