17

able fine veinlets of bornite. Assays from this zone quoted in the Annual
Report of the Minister of Mines for 1923 show that it contains from 5 to 7
per cent of copper with negligible amounts of gold or silver.

The main adit, driven north 160 feet to explore the same fault, is 50
feet lower. Near the portal the fault has been followed for about 30 feet,
but for the next: 80 feet the adit lies a few feet east of the fault. A cross-
cut to the west 120 feet from the portal again intersects the fault and the
adit follows it for an additional 35 feet. A channel sample taken across
the face to include 3 inches of mineralized fault gouge and 33 inches of
slightly mineralized wall-rock assayed: gold, none; silver, 0-20 ounce a
ton; copper, 0-26 per cent. About 80 feet from the portal a short crosscut
to the east follows a strong shear zone 1 foot wide along the north side of a
6-foot dyke of altered and disintegrated diorite. The sheared andesite is
mineralized with bornite and a little chalcocite. A channel sample across
it assayed: gold, 0-02 ounce a ton; silver, 1:08 ounces a ton; copper, 2-42
per cent. There are a number of mineralized cross faults in the adit striking
northeast, one of which, 10 feet from the portal, is younger than the main
vein, and shifts it several feet. A 6-foot diorite dyke that outcrops in the
rock cut on the east side of the portal may be the same one that crosses the
adit 80 feet from the portal, but in the cut it is fresh and unaltered. If
it is the same dyke, then both faulting and mineralization followed the in-
trusion of the diorite.

Banner Homestake Group (9)

References: Ann, Rept., Minister of Mines, B.C., 1925, p. 128. Geol. Surv., Canada,
Sum. Rept. 1925, pt. A, p. 118.

This group of claims, staked by L. E. Moody in 1925, is 9 miles east
of Usk on the north side of Bornite mountain. A branch trail crosses
Chimdemash creek at elevation 2,500 feet and leads south up the mountain
to the camp at 4,000 feet elevation.

The claims are underlain by andesite, volcanic tuffs, and breccia.
Along the face of a steep bluff, at elevation 4,250 feet, these rocks are
traversed by a 4-foot dyke of ‘quartz porphyry. A rusty, altered zone
extends for 2 or 3 feet on both sides of the dyke and at intervals there
are short quartz veins along the dyke. Veins and dyke strike south 60
degrees east and dip 75 degrees southwest. They are exposed for several
hundreds of feet along the precipitous rock slope. Both veins and altered
zone contain a little chalcopyrite and bornite, altered on the surface expo-
sures to green carbonates. A typical sample of quartz and mineralized
tuff assayed: silver, 0-26 ounce a ton; gold, none; copper, 0-20 per cent.

Silver Basin Group (10)

References: Ann. Repts., Minister of Mines, B.C.: 1923, p. 108; 1924, p. 90. Geol.
Surv., Canada, Sum. Rept. 1925, pt. A, p. 118.

The Silver Basin claims at the head of Chimdemash creek, 12 miles

east of Usk, were staked by J. D. Wells in 1923. The claims are mostly

above timber-line and cover the floor of a mountain valley hemmed in on