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Many of the transverse fractures contain quartz veins. In general
each such vein is of uniform thickness through most of its length. It may
end as a single tapering vein or as a fan of divergent narrow branches.
Some are distinctly lenticular, the central part being the widest. Transverse
veins are in general less than 4 feet wide and less than 200 feet long. A few
are locally as much as 5 feet wide.

All the diagonal fractures are quartz filled. In the main they strike
north 70 degrees east to east. They dip southeast to south in the Island
Mountain mine and are approximately vertical in the Cariboo Gold Quartz
mine, and in this respect behave much like the transverse veins. Diagonal
veins are not so plentiful as transverse veins. In the Cariboo Gold Quartz
mine, for example, there are about five times as many veins of the transverse
type as of the diagonal type. Diagonal veins do not display the regular,
closely spaced mode of occurrence exhibited by the transverse veins but
are, on the average, broader and longer. In the Cariboo Gold Quartz mine,
for example, one-third of the larger veins and only about one-sixth of the
smaller ones are of the diagonal type. Diagonal fractures cut through
rocks of dissimilar nature more commonly than those of transverse type.
The longest diagonal vein found so far at the Cariboo Gold Quartz mine
is 300 feet long. It is 5 feet wide at the widest place.

What may be considered another type of fracture is one very closely
associated with the two types previously discussed. These are branch
fractures and are filled with branch veins. Branch veins from diagonal
veins are broader and longer than those from transverse veins. Some
branches from transverse veins swing back to the vein in a few feet to
form links enclosing horses of country rock. Others diverge at various
angles and in general wedge out quickly. Some transverse veins appear to
be branches of diagonal veins. Many diagonal vein branches, however,
occupy curving fractures and die out quickly as irregular tapering wedges.

At the Cariboo Gold Quartz mine the transverse and diagonal veins
occur to some extent in zones each of which may contain half a dozen
or more fairly closely spaced veins. The Sanders vein zone in the mine is
a transverse zone and apparently crosses through the whole width of the
Rainbow member. Individual veins in the zone, however, do not continue
the whole length of the zone. Where this zone crosses the Rainbow member
the latter is divisible into four units and although the vein zone crosses
all the units, individual veins rarely extend through more than one unit.

Another type of quartz-filled fracture is one that closely parallels the
strike and dip of the strata. An excellent example is furnished by the B.C.
vein exposed on the Cariboo claim. At that place the vein has filled and
replaced a fault and associated crushed zone. The vein-filled fracture
clearly crosscuts the strike of the strata at a small angle and is a few
degrees steeper than the dip of the strata. Very few vein-filled fractures of
this type were seen and in general exposures were inadequate for detailed
examination. The B.C. vein is 20 feet wide. There are also several large
and small veins, usually of lenticular shape, paralleling the strata and
possibly in some cases the fissility of the rocks. In most of these cases
the rocks have not been disturbed, as they probably would have been if
there had been any pre-vein fault. The lensy bed veins do not appear to