220

quantities of scheelite, sphalerite, and pyrrhotite. At the junctions of the
two sets of veins there are usually developed chutes of sulphide minerals
of considerable size.

The A veins occur in the “belt of veins” trending northwest and crossing
the creeks near the upper limits of the rich placers. The chutes, therefore,
are strung out intermittently along this belt where the B veins intersect it.

Some of the larger and more barren veins of the A class outcrop
prominently along the valley slopes and on the grassy meadows of the up-
land. Most of the veins of the B class and all the mineralized intersections
are buried beneath drift. Veins of both types have been prospected for
gold, but except for a few small shipments made over twenty-five years -
ago, none of these deposits has developed into a producer.

Free gold may be recovered by panning or rocking the upper, disin-
tegrated and oxidized parts of many of these veins. The amount of gold
thus obtained varies greatly from vein to vein. The veins in most cases
are shattered and the sulphides are oxidized to various depths up to at least
50 feet. Free gold has been found only in this belt of weathering. In
the zone of unaltered sulphides below, the gold values are almost entirely
in arsenopyrite and pyrite.

Selective sampling of the sulphides in the veins showed that: (1) as a
general rule the galena is not auriferous, but carries from one-third to
one-half ounce of silver to the unit of lead; (2) the pyrite carries as high
as $10 a ton in gold; and (8) the arsenopyrite carries gold in amounts
varying up to 135 ounces a ton of pure mineral. The argsenopyrite in
particular, therefore, is sufficieatly auviferous to provide a possible source
of gold for the placer deposits.

CHARACTER OF THE VEIN GOLD

The vein or “quartz” gold, found in the upper, shattered, and oxidized
parts of the sulphide-bearing veins, occurs in various sizes from very
minute specks to pieces worth from $10 to $30!. The latter size is not
necessarily the maximum, but represents the largest recorded piece of gold
derived from the veins during the course of their very limited development.
It is possible that very much larger pieces may occur. Most of the gold,
however, is fine, a considerable part being flour gold, and only a very few
large pieces have been found.

The gold exhibits, to a more or less perfect degree, a crystalline struct-
ure somewhat resembling a mosaic. Some specimens show a distinct
granular structure, due to the presence of a very large number of minute
gold crystal grains. The very fine gold is also crystalline.

Individual crystals and crystal groups are common. Some of the
crystals are nearly perfect, the common forms being the dodecahedron,
the cubo-octahedron, the octahedron, the cubo-dodecahedron, and the
tetrahexahedron. A small tetrahexahedron twinned on an octahedral face
(spinel law) was found during the summer of 1922. Hopper-shaped faces
indicative of rapid growth, are common.

1Macpherson, J. A.: ‘‘Cariboo Placers and Lodes’”’; Min. and Eng. Rec., vol. XXIV, p. 128 (1919).