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380 V. DOLMAGE.

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replaces it, but the epidote is associated with the hematite in a
manner which suggests a nearly simultaneous deposition of both
minerals.

The country rock consists of tuffs which, when not altered, are
a bright red color. Near the vein they are highly epidotized and
silicified, and impregnated with coarse hematite. This zone of
intense epidotization surrounds the deposit for several hundred
feet, extending over to the King vein in its western part.

Summary of the King and Rainbow Veins.—The significant
facts brought out in the observations on these veins are:

1. The King vein has the typical structure, rock alteration,
and mineral composition of the other veins surrounding the
granodiorite stock, and thought to be genetically connected
with it.

2: The Rainbow vein has all the characteristics of the other
type of mineralization, such as the abundant development of chal-
copyrite, hematite and epidote.

3. As the King vein approaches the Rainbow, and comes
within the region which was effected by late mineralization, the
minerals characteristic of this period begin to appear in increas-
ing amounts in the King vein and are seen replacing the bornite
and tetrahedrite of the earlier period. At the extreme west end
where the two veins come almost together the earlier minerals
are almost completely obliterated by the chalcopyrite and hema-
tite of the later period.

These facts are in strict accord with the theory which ex-
plained similar conditions in the Excelsior and High Grade veins.
That is, there were two periods of mineralization, one following
the intrusion of the granodiorite stock which produced the bor-
nite-chalcopyrite ore, and one following the intrusion of the
Bulkley eruptives which developed the chalcopyrite-hematite ore.
The Excelsior and High Grade veins were effected throughout
by both periods of mineralization owing to the proximity of the
dikes, while only part of the King vein is effected by the late min-
eralization.