Custer weekly chronicle. [volume] (Custer City, S.D.) 1890-1931, 1910-08-20

/ Two ui5tiuct properties are now DeInp
worked by the Westinghouse Co. in the
Custer district. Two of them are regu
lar producera of mica-the New Yorl
and Crown-while the others are in
varying stages of development.
The New York, situated 5 miles south.
west Of Custer, the largest producer oi
the company, is on a hogback overlook
ing Hay creek, and about 200 #. aboye
the water level in the creek.
The mine at the present time is 3l5 #
deep. is #. of this depth being account
ed for in slump below the SCOTT. sta
ton. Starting west of the outcrop of a
pegmatite dixie dipping southwest, the
shaft, which is vertical, cuts through the
dixie between the 100 and 200-ft. levels.
From the 800 II. level it will be necessary
to drift in the neighs ,rhood of 150 to
open the dixie. This work is now in
progress. There are openings on the so,
100 and zoo. #. levels, showing continu-
ity of the mica.bearing material, and ex-
tensive surface work has been productive
of large amount of mica.
The dixie is 80 #. thick on the surface,
25 #. on the 100-ft. level, and % #. on
the 200.ft. level. Three to four feet
along the walls is made to produce the
entire mica output of the property, with
the mica content probably little higher
on the hanging wall than on the foot
wall.
The mine is equipped with four 50-hp.
Erie boilers, with fifth now being in
stalled Westinghouse automatic COM
pound engine, IA by "a by IA in, direct
connected to a 500-volt direct-current
generator, of $50 kw., and 300 amperes
a separate lighting set consisting of 6
by in. vertical engine, belted to small
generator an Ingsrsoll-Sergeant straight
line compressor, driven by belt from an
S0-hp 50O-yolt d. c. Westinghouse motor.
A 25-hp. electric hoist is about to be re-
placed by a steam-driven machine of
higher power in order to handle the
cage and cars from the SCOTT. level.
The large generator is used to operate
the compressor, hoist, a triplex-plunger
station pump on the 200-ft. level, the
machinery in the grinding house, etc.
Four Ingersol-Sergeant 24-in. drills are
in constant use, as il a Davis Calyx drill,
for prospecting. This machine is operat-
ing on its first hole, near the level of
Hay creek, about 500 #. south of the
shaft. 1t is expected that this hole will
enter the pegmatite at 200 #. or little
| more.
Ordinary methods ofoverhead stopping
are used in mining the mica, with the ex-
ception that separate chutes are main
tanned for the mica. The mica 10 sorted
from the breakdown and dropped into
these schutes, from which it is drawn
for hosting to the surface. A large por.
ton of the breakdown is used for filling
slopes, 30 that but small percentage is
hoisted. Owing to the character of the
slopes, timbering is confined almost en-
tirely to stulls, and as the slopes are
soon filled, a relatively small number Of
stuls are used.
The mica mined at this property is ordi
narily to 5 ins. thick and 2 to ins. in
diameter. X. P. Harris, assistant super
intendent, is the writer's authority for
the statement that the mica on the 200
#. level was better grade than above,
being less brittle, and thereby giving
better satisfaction in working. This is
turbing atmospheric and surface water
conditions.
(To be Continued.)