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which occur abundantly, especially at altitudes between 4,000 and 4,500 feet
and flow the year round.

PLACER DEPOSITS

The gold placers or pay-streaks occur in five different ways:

(1) They occur in ancient stream gravels resting on bedrock and
in many cases buried beneath great or small thicknesses of glacial drift.
These placers are by far the most important in the area and constituted
the rich pay-streaks in the beds of the creeks, that were mined out, for the
most part, in the early days. The gold-bearing gravels on bedrock vary
from a few inches to 10 or 15 feet in thickness, averaging perhaps 5 or 6
feet, but in places nearly all the gold is directly on, or in cracks and crevices
in, the bedrock. This is specially the case in places where the gravels are
loose, porous, and not clayey. Where the gravels are clayey and contain
numerous partly disintegrated fragments of the country rock, the gold
is likely to be scattered through them.

The gravels on bedrock consist of water-worn but somewhat angular
fragments of the country rock and in many cases include large masses of
rock known as “slide-rock,” apparently an ancient talus. The gravels
were usually described by the miners as ‘flat wash.’ They are character-
ized in places by the presence of heavy minerals and rocks as pyrite, galena,
scheelite, and barytes. Residual gravels, that is, gravels consisting prin-
cipally of a resistant rock such as quartz, are present only in very small
amounts.

The pay-streaks on bedrock are best developed in the narrow, deep
parts of the creeks and do not occur to any great extent in the wider, upper
parts near the sources of the creeks, where valley glaciation has been very
pronounced, nor are they very rich in the wide, deeply-buried lower parts
of the creeks. The pay-gravels, in part at least, were deposited in pre-
Glacial time, but were reworked, to some extent, by stream action in
Pleistocene time.

The gold in the rich pay-streaks was mostly coarse. It was referred
to by the miners as “lead gold,’”’ by which was meant a mixture of well-
worn, coarse gold and moderately fine gold There is comparatively little
very fine gold in the area. It was recognized even in the earliest days that
the creeks containing only very fine gold in the surface deposits were of
little value and that, where only occasional pieces of coarse gold were
found, in the bedrock gravels the pay-streak was not likely to be profitable.
The “leads” of gold in many cases “played out”? upstream and if the lead
or pay ended abruptly it was held that it might possibly be picked up
again higher up the creek, but if it gradually disappeared, chance of finding
further pay was considered small. These theories proved correct only
with respect to a few of the creeks. The pay-streak ended abruptly on
Williams creek above the canyon and was not found again higher up,
probably because the effects of valley glaciation were much greater in the
upper part than in the narrow lower part; consequently the gold deposited
in the old valley bottom was almost entirely removed.