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of the area between Anyox and Maple bay on Portland canal. The
amphibolite intrudes argillites believed to be part of the Hazelton group and
is itself considered to be part of the Hazelton group. The rock is locally
severely sheared. The argillites are in general sheared and folded into tight
folds. Argillite inclusions are numerous in the amphibolite. Some of these
inclusions have been extensively silicified and this suggests strongly that the
amphibolite was the source of the silica.

The chalcopyrite replacement deposits vary in size from vein-like
bodies a few feet wide and a few hundred feet long to large, irregularly
shaped masses as much as 1,000 feet long and deep and as much as 200
feet wide. The deposits in the amphibolite lie parallel to the shearing
and are in general unaccompanied by silicification of the walls. Those in
argillite are accompanied by extensive silicification. Locally the argillite
has been converted into a light-coloured siliceous rock for a distance of
100 feet from the ore-bodies and less marked silicification extends for
another hundred feet or more. That the deposits were formed by replace-
ment is shown locally where the ore exhibits structures formerly present
in the rock.

The ore-bodies of the Hidden Creek mine and the Bonanza mine are
of this type. The Hidden Creek mine has produced steadily since 1914
and since 1920 has produced over 30,000,000 pounds of copper a year.

QUARTZ VEINS

Quartz veins are numerous in Anyox district and on Portland canal
in the vicinity of Maple bay. Some of the veins lie in amphibolite and
others in argillite. The veins in the argillite are commonly parallel to the
bedding, are up to 20 feet or more wide, and some in the vicinity of Anyox
are gold bearing. They consist in general of milky white quartz containing
very little sulphide. One such vein near Anyox is up to 6 feet wide and
was mined for many years to supply quartz flux for the smelter at Anyox.
The flux contained about a tenth of an ounce of gold and about a third
of an ounce of silver a ton. The veins in the amphibolite are of the same
size as those cutting argillite. Some of them contain sufficient chalcopyrite
to give rise to a copper content as high as 5 per cent. In general the veins
can be followed along the strike for many hundreds of feet and some for
more than 2,000 feet.

Quartz veins in amphibolite and at the contact between amphibolite
and sediments are numerous at Maple bay. The veins there commonly
contain chalcopyrite but very little of any other sulphide, and very little
gold and silver. One vein of this type at Maple bay was mined for a
number of years and the ore averaged about 2 per cent copper. Some of
the veins at Maple bay are large and persistent and with a high price for
copper could probably be mined at a profit.

The origin of the replacement and vein deposits is unknown. Coast
Range intrusives occur nearby and no doubt underlie the deposits. These
intrusives may be the source of the deposits, but if so several facts relating
to the Anyox amphibolite are not readily explainable. The amphibolite
certainly caused much silicification of the intruded rocks. The silicified rock
and the replacement ore deposits are closely associated in space. Quartz