Whitesail Lake Map-Area

Limited was formed to take it over. Late in 1950 and early 1951 the
company completed a rough winter road from the head of Francois Lake to
the property, brought in machinery and supplies, and made ready for mining
operations during the summer of 1951. This work coincided with the decision
by the Aluminum Company of Canada to proceed with their power develop-
ment of the area, and in May 1951 the Aluminum Company assumed
responsibility for the completion and maintenance of the road, which would
also serve their operations on Tahtsa Lake.

The ore on the Emerald Glacier property is vein quartz in a shear zone
up to 20 feet wide in which occur lenses of solid sulphides up to 5 feet wide
but averaging 23 to 3 feet in width. The zone has been traced on the surface
for at least 1,000 feet. It strikes north 5 degrees west and dips easterly at 50
to 70 degrees. The host rocks are volcanic and sedimentary rocks of the
Hazelton group that have been disturbed by the emplacement of the granitic
stock on Sibola Mountain.

The vein matter is concentrated along the foot-wall of the sheared zone
which is marked by much gouge. Ore minerals consist of massive sphalerite
and galena with minor chalcopyrite in a gangue of quartz, minor calcite, and
wall-rock.

The shear zone in which the vein occurs lies along a sharp monoclinal
crumple in the Hazelton group strata. West of the crumple the beds are
fairly flat lying but in the vicinity of the vein they dip eastward up to 70
degrees, flattening east of the crumple to dips of 20 to 25 degrees eastward.
That movement has taken place along the bedding planes where the beds
flattened out east of the vein is shown by the 1 inch to 2 inches of gouge
between the beds in this vicinity. A short distance farther to the east the
beds are offset by a north-south fault that is marked by a stream channel.

The vein is strongest in the upper adit or at the crest of the crumple. It
narrows perceptibly with depth and probably dissipates where the beds flatten
out to the east. Only narrow veins were intersected on the intermediate level
and none at all in the lowest adit. It is probable that the lowest adit was driven
well below the main shear structure.

Development work by the Emerald Glacier Company included the
building of roads to the 6,400-foot level and the construction of a permanent
camp at 5,100-foot elevation (see Plate VI B). Underground and surface
diamond drilling amounted to 4,366 feet and underground drifts and crosscuts
totalled 1,448 feet. A raise from the 6,400-foot level to surface is 150 feet
long. A stope was opened on the 6,400-foot level for a distance of 280 feet.
A total of 4,566 tons of ore from development work and the stope yielded
37 ounces of gold, 55,179 ounces of silver, 1,118,809 pounds of lead and

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