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LaRose Mine (Locality 155)

References: Annual Report of the Minister of Mines, British Columbia, 1916, 1917,
1918, 1919, 1920, 1922, 1923, 1925, 1926, 1927, 1928, and 1929; Geol. Surv.,
Canada, Sum. Rept. 1928, pt. A.

The LaRose mine is on the eastern slope of Klayduc mountain, west
of Kitsault river, and about 8 miles from Alice Arm. The mine workings
are about 1,800 feet above the railway and from it can be reached by means
of a good horse trail.

The property was worked in a small way by its owners who made
small shipments of ore in 1918 and 1919. In 1920 the Alice Arm LaRose
Mining Company, Limited, was formed to operate the mine and com-
menced active development in 1925. Ore was shipped in 1926 and 1927,
but since then the property has remained idle. In all, 79 tons of ore
have been shipped and yielded 15 ounces of gold, 15,579 ounces of silver,
and 2,688 pounds of lead.

The country rocks consist of argillite and an interbedded, highly altered
rock that may be a sill of fine-grained andesite. These rocks are cut by
lamprophyre dykes that also cut the mineral deposit. The sediments strike
northwest and dip northeast.

The mineral deposit is a vein occupying a narrow shear zone striking
north and dipping steeply east. The surface expression of the shear zone
is a well-marked, shallow gully along the hillside. The wall-rocks of the
vein, particularly in deeper parts of the mine, are greatly sheared and
especially on the hanging-wall of the vein much movement has taken place
after the vein was formed. Dykes penetrating the vein from the foot-
wall side are cut off by the hanging-wall fault. A wide, sheared zone which
may be a fault with a considerable offset is exposed in a crosscut adit
about 20 feet east of the vein. As the vein dips east it would meet this
shear zone about 50 feet below the adit.

The vein varies from a few inches to 3 feet in width and consists of
quartz, arsenopyrite, pyrite, chalcopyrite, pyrrhotite, sphalerite, galena,
tetrahedrite, native silver, and probably silver sulphides. The vein crosses
the strike of the formation at a slight angle. Where it lies in the highly
altered, presumably igneous rock, the vein is of good size and contains
small ore shoots, but where the vein departs from this rock and enters
argillite it splits and ore is lacking. Ore appears to occur only in the band
of harder rock and this is only 30 feet or so thick. There is reason to
suppose that the vein is offset an unknown distance by the fault a short
distance below the present workings.

Last Chance Group (Locality 188)
Reference: Annual Report of the Minister of Mines, British Columbia, 1916.

The Last Chance group of two mineral claims is on the north bank of
the middle fork of Lime creek. The mineral deposit is a 5-foot quartz vein
in argillite and is sparsely mineralized with pyrite, sphalerite, and galena.