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less to the side. The quartz is also coarsely crystalline in some veins,
but in general it does not show crystal outlines so that the size of crystal
cannot be seen. Ankerite is fairly common in many veins, particularly
along the walls. Some of the narrow veins, a few inches wide, have about
20 per cent ankerite by volume, and branches of the veins appear to
contain more ankerite than the parent veins. Many veins have little or
no ankerite and those containing much ankerite have in general very little
gold. Calcite was seen in veins only where they cut beds of limestone.
Thin foils of sericite occur in some veins. Those containing much sericite
have very little gold. Gold occurs free throughout the veins, but is
especially abundant in the nests of the lead-bismuth sulphides. It varies
greatly in fineness. Pieces weighing } ounce have been found and specks
tosooinch in diameter have been seen microscopically.

Another characteristic of the veins is that they have been shattered
so much that it is difficult to obtain large solid hand specimens. In min-
ing, veins break up into small pieces.

The strike fault veins are not numerous and are poorly exposed.
Only one such vein, the B.C. vein, was seen underground. It contains
pyrite in quartz and in mineralization appeared to be like scores of trans-
verse or diagonal veins. The B.C. vein, so far as known, has much lower
values in gold than the normal pyritic transverse or diagonal veins, but it
is not located in the richest part of the gold belt and, therefore, should
normally have a low gold content. Veins of this type have not been devel-
oped sufficiently to prove that they are of low grade or to prove that
they are uncommercial.

Only a few bed veins were seen, some of these are quite thin and
short, but most are wide lenticular bodies. These in general consist of
quartz with no pyrite and no gold. Development work done on veins
of this type is too meagre to give a reliable picture of their value. Some
have been deformed with the adjoining rock and, therefore, appear to be
earlier than the transverse and diagonal veins. Some small bed veins
join with transverse veins and appear to be of the same age and are
mineralized in the same way.

Uglow divided the veins into A and B veins and stated that the B
veins were higher grade than the A veins. The B veins would include
the transverse and presumably also the diagonal veins. The A veins
would include the strike fault veins and the bed veins. Many of the
large A veins lie outside of the gold belt and are not well mineralized,
but scant mineralization also characterizes many veins truncating the
strata at various angles outside of the gold belt. The writer feels that
so far as the gold belt is concerned there is not enough data to classify
the veins paralleling or nearly paralleling the strata as being uncom-
mercial.

REPLACEMENT DEPOSITS

The other main type of deposit is one formed by replacement of lime-
stone. This type of deposit was discovered in the Cariboo in 1933. The
largest so far found is in the Island Mountain mine. The ore of this type
is in general higher grade than the vein ore and commonly assays 2 ounces

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