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Quartz veins are numerous in many parts of the area. Those cutting
the Hogem batholith are for the most part barren, and appear to be high-
temperature veins grading into quartz-feldspar pegmatite dykes. A large
carbonatized shear zone on the Elizabeth group north of Osilinka River in
the interior of the batholith contains many quartz veins, some of which
carry gold and silver. The nearby ‘Chief Thomas’ vein is 6 to 10 feet wide,
at least 300 feet long, and carries chalcopyrite, pyrite, bornite, and a little
gold and silver.

Quartz veins are particularly numerous in an area extending northwest
from Tutizzi Lake along the west border of the map-area to Lay Creek and
continuing into McConnell Creek map-area to the west as far as Goldway
Peak and the headwaters of Wrede Creek. The larger veins are, in general,
massive white quartz, barren of sulphides or precious metals. Smaller
veins, stringer lodes, and silicified shear zones exhibit wide variations of
mineral content. The boss-like quartz body exposed on Porphyry Creek
contains pyrite, magnetite, and molybdenite; the nearby Croydon group
veins and stock-works contain massive pyrite, chalcopyrite, molybdenite,
and magnetite, with fair gold content; the veins of the Shell group, whose
main showings lie just west of the map-area, contain pyrite and chalcopy-
rite, with considerable gold and, in places, minor magnetite and erythrite.
A little cobalt bloom was also observed coating fractures in small quartz
veins in hornblende diorite east of Croydon Creek. Deposits up to 15 feet
thick and 34 mile long, rich in magnetite, with minor pyrite, pyrrhotite,
chalcopyrite, and gold, are exposed along the west edge of the map-area
near Croydon Creek. North of Tutizzi Lake, several of the quartz veins
contain crystalline galena, commonly accompanied by chalcopyrite or
specular hematite. Similar veins cut hornblende diorite and appinite west
of Abraham Creek.

The mineral showings on the Vega property occur in intensely faulted
and sheared andesites of the Takla group. The andesite contains rounded
fragments of feldspar porphyry. Chalcopyrite, pyrite, and bornite are
disseminated through the andesite and concentrated along calcite veinlets.

The workings on Thane Creek expose a silicified shear zone about 4
feet wide in amphibolitized andesite near the eastern contact of the Hogem
batholith. The zone carries pyrite, chalcopyrite, specularite, and magnetite,
and a little gold.

Lenses of pyrite and arsenopyrite up to 50 feet long and.9 feet wide in
sheared greenstone near the contact of a sill of granodiorite porphyry are
exposed by the Pluto workings. They are reported to carry some gold.

The late Paleozoic rocks outcropping in the Lay Range contain rela-
tively abundant, disseminated, finely crystalline pyrite, which appears for
the most part to be the product of general metamorphism rather than
hydrothermal mineralization. Stringers and veins of quartz and calcite
are numerous, but most of them are small and discontinuous. In these
strata, several distinct types of mineralization are represented. All deposits
lie near small igneous bodies that appear to be related to the Omineca
intrusions. The most widespread type of mineralization is represented on
the Jupiter, Polaris, and Stranger showings by highly brecciated quartz-
calcite veins or fracture zones associated with much black, lustrous graphite