38

At the location of the open-cut and two adits the strike and dip of the
quartz-albite dyke are indeterminable, due to faulting and a drift cover.
Farther east, where exposed on the side of a steep hill, the dyke has a
width of 40 feet and strikes south 80 degrees west. An adit was driven at
the foot of the hill at an elevation of 550 feet for 40 feet in a northwest
direction to intersect the dyke. The adit is heavily timbered and wholly in
drift, with andesite showing at the face.

Grotto Group (29)

(See Figure 6)

References: Ann. Repts., Minister of Mines, B.C.: 1929, p. 152; 1931, p. 71. B.C. Dept.
of Mines, Bull. No. 1, 1932, p. 56.

The Grotto group, owned by G. Alger, J. Bell, and Lee Bethurem of
Usk, is on Hardscrabble creek about one mile west of the Canadian
National railway and about 14 miles from Pitman flag station. The
workings are on both sides of the stream at an elevation of approximately
650 feet, and are reached by a good trail which runs along the north side
of the creek across the Diorite property.

Thirty-five feet from the water’s edge on the north side of Hard-
scrabble creek an adit has been driven for 96 feet to explore a quartz vein
that occurs along the contact of a 12-foot andesine diorite porphyry dyke
intrusive into andesite. Vein and dyke strike northeast and the dip of the
vein ranges from vertical to 60 degrees northwest. The vein maintains an
average width of 12 inches for over 100 feet, and the quartz is heavily
mineralized with pyrite and a little specularite. Twenty-five feet from the
portal of the adit the vein branches, one part crosses the dyke and the other
part follows the west side of the dyke. The main adit follows the west side
for 65 feet, but no vein quartz is present for the last 20 feet of this distance.
There is, however, a shear zone along the line of contact along which the
vein might be expected to reappear. At 65 feet from the portal the adit
swings across to the east side of the dyke and follows the main vein for a
few feet until it likewise pinches.

A small, stock-like body of andesine granodiorite is exposed on the
stream bank 80 feet east of the portal, but whether it is older or younger
than the andesine diorite porphyry dyke is not known. ‘The andesine
granodiorite is cut by a 2-foot dyke of lamprophyre.

The writer took a 12-inch channel sample across the vein from the
roof of the adit which assayed: gold, 0-26 ounce a ton; silver, 5:30 ounces
a ton; copper, 2 per cent. A hand specimen picked from the dump assayed:
gold, 0-06 ounce a ton; silver, 17-44 ounces a ton; copper, 0-82 per cent.
Both samples were well mineralized with pyrite and contained a little
bornite and specularite.

About 300 feet farther upstream a quartz vein of similar appearance,
which outcrops on the south shore of the creek, has been traced in a south-
west direction for 40 feet. The vein pinches out near the face of a 26-foot
adit where the fault along which it occurs turns southeastward to join a
cross fault. Its continuation to the north is hidden by water and boulders.
The vein has an initial width of 6 inches at the water’s edge, but widens to
9 inches in the adit. The enclosing andesite country rock is cut by a 6-foot