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driving of the main crosscut adit at elevation 2,000 feet. This adit was
continued in 1920 from the 200-foot mark to nearly 500 feet. Some
drifting was done on the main vein by W. S. Harris in 1925 and by
E. G. Brown in 1927. The property was optioned to Federal Mining and
Smelting Company for a short time in 1928. Mohawk Mining Company,
Limited, continued underground development work in 1928 and shipped
69 tons of hand-sorted and hand-jigged silver- lead- zinc ore. An additional
30 tons of ore was shipped in 1929. Operations were suspended in the
autumn of 1929 after completing 745 feet of crosscutting and 940 feet of
drifting in the main adit, with a 175-foot air raise to the surface at a
point 885 feet from the portal. Above the main adit a 38-foot shaft was
sunk on the main vein, with a 130-foot drift and two small stopes. Another
shaft, now water filled but reported to be 50 feet deep, was sunk on an
upper vein at elevation 2,225 feet, about 850 feet northeast of the 38-foot
shaft. .

The veins occur along faults in intensely altered and recrystallized
tuff and sandstone beds, which are intruded by coarsely crystalline, grey
granodiorite (See Figure 6). Frequently the veins lie in faults along the
contact of the altered sediments and the intrusive granodiorite or in the
altered sediments close to the granodiorite, and narrow after a few feet
on entering the intrusive. The granodiorite is part of the boss-shaped
body 1 mile in diameter that forms Four Mile Mountain. The main
workings are in the tip of a tongue-like body of the altered sedimentary
rocks that extends eastward into the granodiorite. The shape of this body
is open to question, but judging from the surface outcrops and the under-

round exposures it is approximately 500 feet across from north to south

in the vicinity of the workings and its outline is indented by abundant
apophyses of the granodiorite. The sediments are also cut by a few small
dykes of biotite aplite, which are exposed in the main adit. Three veins
striking northeast and dipping from 380 to 65 degrees southeast are
prospected by the workings in the tongue-like body of altered tuff and
sandstone. A fourth vein, also striking northeast and dipping about
60 degrees southeast, is prospected by a shaft and trenches in an isolated
body of altered tuff about 800 feet northeast of the main vein exposure.
The veins range from 4 inches to 4 feet in width and from 100 to 450 feet
in length. They are composed of a gangue of banded quartz and siderite,
for the most part very sparsely mineralized, but there are a number of
small, rich ore shoots of erratic distribution. The ore minerals in order
of abundance are, jamesonite, sphalerite, pyrite, galena, and tetrahedrite.
Assays show a high silver content and appreciable amounts of antimony
in the high-grade shoots, in addition to lead and zinc.

The main vein is exposed by trenches and open-cuts for 210 feet
along the surface at elevation 2,080 feet. To the southwest the vein
terminates at a cross fault that strikes north 80 degrees east and dips
30 degrees southeast. The fault is at the east end of a 140-foot rock
trench 12 feet deep in the altered sediments. Thirty feet north of the
fault, a shaft inclined at 65 degrees is sunk 38 feet on the vein. From
the bottom of the shaft a drift follows the vein northeast for 130 feet.
The vein ranges in width from 12 inches at the shaft to 4 feet at the
north face of the drift. The quartz gangue carries from 2 to 10 per cent