INHERENT QUALITIES 127
an
inexperienced eye, diamonds have a grain along which they can be split
as wood is split, only much more evenly and exactly. This grain is
parallel with the faces of the octahedra. Advantage is taken of this to
save material and the labor which would otherwise be expended in
grinding away superfluous parts, to eliminate interior flaws, and also
to improve the color, for by judicious cleaving a number of parts of a
crystal may be made to yield a finer color than that of the crystal in
its entirety. To be a good cleaver one must be familiar with rough
diamonds and have good judgment; the operation itself is simple. Having
studied a crystal and decided just where and how to cleave it, the
cleaver takes the edge of another rough diamond fastened in a
convenient handle, and grinds it across the edge at the point where the
stone is to be split, until there is an incision proportionate to the
size of the crystal being operated on. He then uses other " sharps," as
the cutting edges are called, until the incision has the appearance of
a V-shaped nick. Placing the blunt edge of a flat piece of steel like a
short ruler, in the incision, he strikes the other edge a smart blow
with a small hammer, and the crystal divides, the two planes of the
cleft smooth and shining as glass. After examining the pieces, he
places them in the little lock-box always before him, lights a fresh
cigarette, and picks up another crystal for examination. About
twenty-five per cent, of the diamonds found require cleaving.
Another
form of cutting is the " rose cut," used principally for cheap cluster
work in countries where the people are not as critical and have less
money to spend than those of the United States. Rose cut diamonds are
high
