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Mr. Bowman’s REPorRT ON CARIBOO DISTRICT. 1886

Mining developments.

Surface Geology.

The ancient streams.

Drift.

Interior Lake.

Terrace formation.

Different kinds of
placers.

Quartz mining and
milling.

Failure and cause.

Experience.

Character of auriferous
placer regions.

resting upon the shoulders of the same crystalline core as the gold and silver-
bearing rocks of the south.

Before the railways disclosed the latter’s wealth—between 1870 and 1880—
Cariboo had already yielded a great amount of treasure from the easily devel-
oped placer mines. But to proceed further, now following the example of
the later developed gold and silver-bearing districts mentioned, to the
successful exploitation of the lodes from which in part these placers have
been originally supplied, will require an equally intelligent investment of a
reasonable amount of capital, and possibly also the facilities of transport
afforded by a branch railway.

From the Round Top, near latitude 53° N., longitude 121° W., the char-
acteristic features of the region disclose themselves in the flat expanse of
Snow-shoe Plateau. It is free from timber, green and grass-covered—a
prairie remnant of the dry area extending over the entire plateau of the
cordilleras to the southward. Its surface is soil-covered—some of it detrital,
and suggestive of the levelling presence of water in post-glacial times. From
the plateau, or parallel swell, streams falling both eastward and westward
have intersected the gold-bearing zone, or zones, of the fissured slates.
Debouching into what were formerly swampy valleys (miocene, lignite-
bearing), and more recently lakes (pliocene gravel ranges), we see these
water-courses blending on the horizon with the volcanic outflows which sep-
arate here as in California, the materials belonging to an older drainage
system from those of the recent. Next all the phenomena of the drift are
seen altering, and hiding, the channels so interesting to the gold miner. The
pay dirt passes under and mingles with the deposits of a vast interior lake,

The drainage of this lake, in recent times, has terraced the British Colum-
bia plateau from the inner margin of the Coast Range to the Rocky Moun-
tains. As in the mining region, however, the voleanic matter is wanting, it
appears that the gold miners of the country are working indiscriminately in

placers which date, probably, from the miocene period down to the present.

Quartz mining has never yet been permanently established, nor indeed
fairly tried in the Cariboo District. In 1877 some attention was drawn to
the quartz veins of Cariboo, and a good deal of capital was invested in quartz
mills. There was, however, a lacking element which thwarted success. As
to the nature of this obstacle, there has been much difference of opinion. Jt
is certain that the larger investments have all, so far, proved disastrous. It
is also certain that iron pyrites was worked which contained very little gold;
while other samples of pyritous quartz, containing as much as $20 per ton of
finely disseminated gold locked up in the sulphuret, were worked in consid-
erable quantity as though they had been free milling ores. Owing to the
want of concentrating machinery, the pyrites passed off; and without
wasting, or chlorinating, or other appliance to save it, of course, the gold
contained in the pyrites was lost at the same time. As it has never been
decided to the satisfaction of all concerned on whom the blame for the fail-
ure of this attempt should be placed, there appears to have been a tendency
in some quarters to conclude that the quartz lodes themselves are worthless—
a tendency which the writer cannot too strongly deprecate.

Inquiring into the real causes of failure, it will not be out of place to recall
well-known facts. In the first place, it is to be observed that the Cariboo
quartz excitement of 1877-8 followed upon the heels of the Washoe bonanza
developments. Cariboo inherited some of the methods of handling stocks
connected with the latter. The Washoe method worked badly as applied to
British Columbia quartz. Secondly, it is undoubtedly true that the gold-
bearing quartz veins, or veinlets, which have contributed to the wealth of
the placers are, to a considerable extent, disseminated throughout the slates.
Net-works of small fissures of this character are quite usual in slate forma-
tions, and are found here precisely as in other gold regions. The auriferous
fissures have been exposed in detail by the disintegration of the friable rock,
in combination with the conditions of sluicing.