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Chuchi Tungsten Showing

This showing lies 9 miles south of the east end of
Chuchi Lake at the contact of a small granitic stock with
andesite of the Takla group. The deposit consists of scheelite,
powellite, molybdenite, and chalcopyrite disseminated throughout
a fracture zone at least 12 feet wide in silicified andesite
at the granitic contact. Iwo grab samples assayed 0.075 per
cent WO3, 0.015 per cent MoSe, trace of gold, and 0.70 ounce of
Silver a ton.

Nina Copper Showing

This showing occurs near the summit of the peak north
of the east end of Nina Lake. A trail up Nina Creek to Nina
Lake and beyond reaches a point within 2 miles of the showing.
The deposit consists of a mineralized zone, at least 8 feet wide,
containing malachite and pyrite with minor azurite. It lies in
a 200-foot band of sheared, carbonatized, silicified, and
pyritized interbedded argillite and andesite of the Cache Creek
group. The mineralized zone is also much broken by faults and
veined by quartz. A grab sample assayed 4.83 per cent copper
and 0.005 ounce of gold a ton.

PROSPECTING POSSIBILITIES

Placer mining has been an active industry in Manson
Creek map-area since 1870, but in all this time comparatively
little lode prospecting has been attempted with a knowledge of
the structural geology of the area. Altogether only a score
of mineral showings havé-yet-been-found. The present study of
the known lode and placer deposits and of the regional geology
of the area has pointed to certain definite conclusions with
respect to the source of the deposits, and these may serve as
a guide to future prospecting. In the course of geological
field work during 1944, four promising lode prospects were found.

Many of the lode and most of the placer deposits in
the area are related to the Manson fault zone and subsidiary
fault, shear, and fracture zones. ‘These, apparently, provided
channelways for mineralizing solutions, and lode deposits were
formed wherever other conditions were favourable. The zones are
readily recognizable due to the characteristic alteration of
their Wall-rocks to a butf-coloured aggregate of carbonate,
quartz, chlorite, and mariposite. Probably much of the placer
gold along Germansen and Manson Rivers and their tributaries
came from these carbonate rocks and their associated auriferous
quartz veins. The most likely areas to prospect for placer are,
consequently, those where creeks and old channels cross bands
of carbonate rocks containing quartz veins.

Carbonatized fault and shear zones, other than the
Manson fault zone, also merit future prospecting. The Nina
copper deposit occurs along one such zone.

Several lode deposits have been found in shear or
fracture zones close to, and in, intrusive bodies. They have,
presumably, originated from solutions related to the Omineca
intrusions. It is, therefore, apparent that contact zones of
these intrusive rocks, especially where shear and fractures
zones occur, should be favourable prospecting ground.