The Western news., 1904-12-07
MINES AND MINING NEWS
ITEMS OF INTEREST GATHERED
DURING THE PAST WEEK.,

|" booHoS "OHtoUd anu OTcSOH-
Mine Operations Of British coIum.
bia Are Brisk-Many Accidents and
Personal Events.
Waldemar Lindgren of the United
States geological survey, assisted by
q. w. Stose and H. R. johnson, under
took a geological reconnaissance in
1899 across the bitter Root range and
the Clear water mountains in Montana
and Idaho. Mr. Lindrgen wrote re-
port Of the work, giving particular
attention to the mineral deposits of the
region studied, and it is now available
as professional paper No. ~, and may
be obtained free of charge, on applica-
tion to the director of the United
States geological survey, Washington.
D. G., It is the only paper ever pub
Gshe ! on the geology Of the district.
The rsgion described in this report
is bordered on the south by the Salmon
river and on the north by the north
fork of the Clearwater. The Bitter
Root range, which attains an elevation
of 1900 feet, merges into the great
.diss,c ID high plateau of the Clear
W. ter mountains. These descend rather
abruptly to the plateaus of the Camas
prairie and Cold Springs prairie, which
form part of the Columbia river lava
plateau. This plateau has general
elevation of $500 to 5000 feet, and is
built up of horizontal lava flows. From
great glacial cirques in the western
slopes Of the Bitter Root range the
Salmon river and the several forks of
the Clearwater river find their way
westward through canyons from 5000
to 5000 feet deep. The canyon of the
Salmon is especially remark able for it's
great length and depth.
The area indicated forms a wild and
very sparsely populated mountain re-
gion, which is heavily timbered except
on the highest ridges. The geology of
the region is comparatively simple.
The main Bitter Root range and the
larger part of the Clearwater noun
tains consist of massive biotite gran
ite, or, to define it more correctly, of a
quartz monzonite, which is the north
ward continuation of the great batho-
lith of the same rock that occupies so
large an area in southern central
Idaho. A very remark able fault of ex-
ceptional lentgh and displacement sep
arates the eastern slope of the Bitter
Root mountains from the valley Of the
same name.
The valuable minerals contained in
this area are confined chiefly to the
western slope of the Clearwater noun.
tains. The most important are the
gold deposits, which occur in the
fissure veins and gravels. At the foot
of the Bitter Root mountains, some -
miles north of Hamilton, Mont, is the
remarkable Curlew mine, where body
of galena was found in fissure that
had limestone and quartzite as it's foot
wall and the gravels of the Bitter Root
valley as hanging wall. On the upper
south fork of the Bitter Root river
prospects of copper, sivler and silver
lead ore have been worked. Hughes
creek, in the same vicinity, contains
gold bearing gravels which have been
worked for many years.
Elk City, whree mineral deposits
were discovered in 1862, is the centre
Of the gold mining industry on the
west slope. Gold to the value of sew.
eral million dollars was extracted there
from late tertiary bench gravels, and
placer mining is still prosecuted on
small scale. Quartz veins have also
been opened in the old mining district.
The we'll defined quartz veins of
Buffalo Hump, discovered in 1897, are
actively worked, though not on a very
large scale. These deposits occur in
granite rocks, accompanied by contact
metamorphic states. Florence, loca ted
40 miles southwest of Elk City, is an
other of the old placer camps, dis
covered about 1861. The gravels were
rich and the camp has yielded gold to
the value of many million dollars. At
preesnt few placer and quartz mines
are worked there also. Pierce City,
on OrofinO creek, about SO miles north
northwest of Elk City, is also a we'll
known placer camp, discovered in
1861, and worked continuously since
then. The present yield from these
placers is probably about $4,000 per
annum. Ths gravols occur as creek
aluvium and as benches up to 500 feet
above the persent drainage level.
Quartz veins have also been found near
Pierce, and many of them are now
worked on small scale. The veins
occur on gneises and chists. The total
production of this gold. bearing region
is at the present time probably about
100000 per annum.
Coal of fair quality has been found
on the upper South Fork of the Bitter
Root valley, and the beds are here as
sociated with rhyolote. The develop.
ments have not yet shown the extent of
this occurrence. Ignite of fair quail
ity aslo occurs on Orofino creek below
Pierce, and is associated with basalts,
but the beds are probably not thick
enough to make development profita-
BILE.