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L and L Group (Locality 85)

References: Annual Report of the Minister of Mines, British Columbia, 1919, 1922,
1923, 1924, 1925, 1926, 1927, and 1928; Geol. Surv., Canada, Memoir 159.

The L and L group of mineral claims is on the south side of the glacier
on the north fork of Glacier creek. The camp and workings are at an
elevation of 3,400 feet. The country rock is augite porphyrite. The con-
tact of the augite porphyrite with sediments of the lower part of the
Hazelton group is on the opposite side of the glacier and appears to dip
gently northward.

Development work has been concentrated on a northwesterly striking
vein that dips 70 degrees southwestward. The vein is 3 feet wide and con-
sists of quartz with pyrite, chalcopyrite, arsenopyrite, pyrrhotite, sphaler-
ite, galena, tetrahedrite, and an unidentified lead sulphantimonide. The
most plentiful sulphides are pyrite, galena, sphalerite, and tetrahedrite.
One shoot of ore has been discovered in the vein. It is 1 to 2 feet wide,
120 feet long, and extends from the surface to a depth of at least 120 feet.

Three drift adits have been run in southeasterly directions. The upper-
most or No. 2 adit follows the ore-shoot for 120 feet to where, though the
vein continued, the ore-shoot ended. Believing that the ore deposit at
this point had been offset by a fault those responsible for the development
work drove crosscuts to both sides. Eventually the drift was continued
along the southeasterly course and some ore, which may be the northern
end of a second ore-shoot, was found at the face of the drift. No. 1 adit
is 100 feet northwest and 60 feet below the upper adit. This adit for most
of its length follows the vein. The ore-shoot is only 60 feet long on this
level. Stopes extend from No. 1 adit to the surface. The lowest or No. 3
adit is 320 feet northwest and 160 feet below the upper adit. It follows
the vein but the ore-shoot is not present.

Evidence furnished by polished specimens of the ore suggests two
periods of mineralization. The first resulted in a vein of quartz with
pyrite, chalcopyrite, and arsenopyrite, and some galena and sphalerite.
The minerals of the second period of mineralization are chiefly galena and
tetrahedrite deposited in fractures in the earlier, lean, vein matter. The
ore-shoot consists chiefly of minerals formed during the second period of
mineralization. Specimens of vein matter from the lowest adit show nar-
row stringers of galena and tetrahedrite traversing the earlier vein matter,
and suggest that commercial ore extends downward nearly to this adit.
Ore specimens from near the surface contain an unidentified lead sul-
phantimonide. It occurs in narrow veinlets and is distinctly later than any
other mineral in the vein.

Shipments of ore were made from the property in 1924 and 1928. A
total of 59 tons of ore was shipped, yielding 0-1 ounce gold and 160 ounces
silver a ton, and 138 per cent lead.