portant.
They mostly were used for gem polishing. But during that year certain
engineers, planning to make a survey for a tunnel through one of the
mountains of the Alpine range, asked a Swiss watchmaker and diamond
expert for advice. That individual, the famous M. Leschot, took the
problem home with him and the next day presented the engineers with a
plan. It was a plan for the diamond drill.
This
opened a new wide field for a previously profitless by-product, since
much of the diamond material, then equivalent to present-day
"industrials," was too flawed and intrinsically dirty even to polish
into gems. Later the Diamond Corporation became interested and today
the industrial diamond accounts for at least 15 per cent of its income.
The
industrial boom received a further boost in popularity during the
years following the first World War. This was because steels of greatly
increased hardness came into general manufacturing use, and also the
demands for more precision in tooling and grinding became impeperative. Only the diamqnd could answer the demands.
The
industrial isn't ugly, it simply has not the potentialities of
brilliance. It is true, of course, that in the past some stones now
called industrials were used as gems. But the run of the mine provide
very off-color stones, usually brown or a sickly yellow, sometimes
green or gray or even rose-colored. The industrial also is imperfectly
crystallized, so that its malformed planes of cleavage do not
allow light to flash through the stone after it has been cut and
polished. For the same reason, however, it is a tough stone.
Its
colors, incidentally, have played a peculiar part in the preferences of
industrial engineers. The emery wheel is a vital key to the mass
production of automobiles, making (until the second World War) the
automobile industry
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