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to a considerable degree with the increase in size of the
intrusive bodies. On Hudson Bay mountain where the main
intrusive body is not exposed but is probably fairly large,
deposits have been clearly shovm to have vertical depths of
over 600 feet and a similar range away from the intrusive body,
assuming that it occupies the core of the mountain. The lengths
of the deposits are over 3, 700 feet and the vertical ranges from
end to end over 1,200 feet. The dimensions are probably much
greater over the tops of intrusive bodies as on Hudson Bay
mountain than on the sides of deeply eroded masses such as
those of Rocher Déboulé mountain.

’ The largest mineral deposits have been found on or near
the largest mountains, such as Hudson bay, Rocher Deboulé,
Fourmile, etc., and near the largest intrusive bodies. On smaller

mountains, notably in the southern part of tho Babine range, and

near the smaller and the finer grained intrusive bodies (porphyries

and rhyolites) much development work on many deposits hes failed
to yield deposits of a size comparable with those on larger
mountains.

On Rocher Dcboulé mountain some of the mineral deposits
occur well within a large granitic body. Some of these are of a
type ee commonly is formed where low temperatures prevail.
Therefore, the granitic mass must have solidified and cooled
considerably before the deposits were formed. The deposits are
thus considerably later in age than the enclosing granitic rocks
and must be related to some other deep-seated source. Thus there
are indicated possibilities, not only for Rocher Déboule mountain
but for other parts of the district, for the occurrence of
deposits with different relationships from those commonly found.

The distribution of deposits in any one locality and

the grade of ore in individual veins have in the main shown that