CUTTING DIAMONDS
Into
Louis Van Berquen's head one day came the fantastic idea of grinding
off the upper and lower points of an octahedral diamond (having eight
triangular faces) to produce a symmetrical gem of a new and artificial
design. Where the points had been, would now lie two artificial facets.
To make it possible Berquen conceived a new technique of cutting. He
took the fine sharp dust of a crushed diamond and sprinkled it on a
wheel. Then coating the wheel with oil, he held the corner of another
diamond against it while it turned. Berquen's primitive cut, admired
and imitated everywhere, was fashionable in Europe for a hundred years.
His dust-sprinkled wheel is the basic tool of the cutting industry
today.
In
Amsterdam competent mechanics lay the stone bare by removing the outer
crust, and then a jury of diamond-cutters set upon it to decide how it
should be cut. Diamonds are cut in four shapes—the brilliant, the
rose, the table, and the brilliolette. It is hardly necessary to
describe the latter two, as they have gone out of fashion and are now
rarely seen. The rose diamond is flat on the under surface, and cut
into innumerable facets on the upper. This form of diamond is rarely
seen in this country. It is, however, the best form in which to cut
diamonds of small depth, and has been adopted for some large gems, such
as the Orloff and the Florentine, with fine effect.
The
table cut was not abandoned until another lapidary invented the rose
cut a century later. This was a diamond shaped like a hemisphere, with
a flat base from which arose twelve triangular facets, ending in a
point at the top. The
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