With an iron pestle, and passing it when
crushed, through a series of sieves in which the gold, too large to fall
through, is held.
To estimate roughly the worth of a reef in which only fine gold is visible
it is necessary to take several samples along the outcrop, "dolly" them,
and wash the powdered quartz by means of two iron dishes, from which the
light material is floated off, leaving the gold behind. From a series of
experiments an idea can be formed as to whether the reef is worth further
work.
It will be found on napping a reef, that the gold occurs at more or less
regular intervals. This deposit of gold in the surface outcrop is the top
of a "shoot" of gold, which may be followed down on the underlay for many
feet. And this peculiarity in the distribution of the metal has been the
cause of much disappointment and misunderstanding.
Having determined that your reef is good enough on the surface, the next
thing to be done is to ascertain, by means of cuts and shafts, its nature
below the surface. This may be done either by an underlay shaft, which
follows the reef down from the surface, or by a vertical shaft, sunk some
distance away from the outcrop, to cut the reef perhaps one hundred feet
below.
