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QUEEN CHARLOTTE MINING DIVISION

(7) Iron Duke Mineral Claims, Louise Island
(See Figure 3)
LOCATION AND HISTORY

The Iron Duke mineral claim group is owned by Messrs. Rogers,
Benson, and Larsen and is situated on the south slope of a ridge rising from
the north shore of Louise island. <A trail to the claims commences on the
south shore of Cumshewa inlet at a low point from which a bearing on the
Indian village on the north shore is about north-northwest (335 degrees
magnetic). The trail is about 2 miles long, follows a curving course up-
wards around the east end of a ridge, and ends on the southern slope at the
mouth of a tunnel at an elevation of about 1,100 feet.

The property appears to have first attracted attention in 1911; has
since changed ownership and was surveyed in 1921. It consists of a number
of claims, but work which consists of shallow trenches and a tunnel 69 feet
long has been largely concentrated on one claim. The property has been
referred to in the following reports:

Ann. Repts., Minister of Mines, 1911, p. 77; 1913, p. 104.

Lindeman E., and Bolton, L. L.:‘‘ Iron Ore Occurrences in Canada’’; Mines Branch, Dept.
of Mines, Canada, vol. 2, p. 18 (1917). The property is referred to twice, once as the
Kildoo, Indian Woman, Darling, and Edgar claims, and once as the Cumshewa iron
deposits.

Whittier, W. H.: “An Investigation of the Iron Ore Resources of the Northwest’’; Univ. of
Washington, Bureau of Industrial Research; Bull. No. 2, pp. 68-70 (1917). The amount of
ore present above the lowest outcrop is estimated to be 1,610,000 tons.

Clothier, G. A.: ‘“‘North-western District (No. 1)’; Ann. Repts., Minister of Mines, B.C.,
1918, pp. 4041; 1921, p. 39; 1922, p. 41. Relative positions and the sizes of various
exposures of magnetite are given.

Stansfield, A.: ‘‘The Commercial Feasibility of the Electric Smelting of Iron Ores in British
Columbia’’; Dept. of Mines, B.C., Bull. No. 2, p. 31 (1919). An estimate made by B. L.
Thane and Company, San Francisco, is that the deposit contains 570,000 tons of iron ore
and probably 344,006 tons more.

DESCRIPTION OF ORE OCCURRENCES

The magnetite deposits occur on a steep slope which faces south and
is surfaced with a nearly continuous cover of drift, so that natural outcrops
of magnetite or country rock are almost lacking. Numerous, short, shallow
trenches have been dug, but at the present time, whatever may have been
the case originally, only a few of these reach bedrock. The strata appear
to be wholly intrusive porphyrites presumably belonging to the widespread
Triassic rocks, which in the general vicinity include limestone and other
sediments, are cut by numerous dykes, and have been invaded by batho-
lithic bodies of granite, granodiorite, etc., of late Jurassic or early Cretaceous
age. The magnetite deposits as indicated more particularly in the tunnel
on the property are replacement. bodies probably associated in origin with
the granitic rocks exposed not far away. No limestone was seen in the
immediate vicinity. The magnetite has replaced porphyrites and these
rocks close to the magnetite bodies are much altered and have been impreg-
nated with epidote, pyrite, magnetite, garnet, and other minerals. =

The exposures of magnetite are almost wholly confined to a zone 360
feet long in an east and west direction with a maximum breadth of 100 feet.

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