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undergoing total reflections, the light emerges from the stone on which the changing flashes of fire are seen.
Modifications of the brilliant cut
The
brilliant cut has many modifications. The double brilliant or Lisbon
cut has 74 facets. The half brilliant is a simple form, used for
smaller stones. The trap brilliant or step brilliant has 42 facets. The
Portuguese cut has 2 rows of rhombohedral and 3 of triangular facets on
both crown and base. The star cut has a hexagonal table bordered by 6
facets in the shape of equilateral triangles, forming with the table a
six-rayed star.
In
cutting, attempts are also made to retain the maximum size of the stone
but symmetry and beauty of form are not to be sacrificed. The brilliant
cut is also used for ruby, sapphire, emerald and zircon. They are also
cut with square outlines and fewer facets as in emerald. Stones are
also cut in numerous other shapes, e.g. oval, elliptical, pear-shaped,
etc. .'Melee' is a term applied to stones cut from small fragments of
the diamond. 8-16 stones make a carat and the stones have 58 facets.
Still smaller stones are called small 'melee', and 400 stones make a
carat.
Coloured stones—Step, trap and cushion cuts are commonly used with coloured stones, e.g. emerald and tourmaline.
Cutting of Gems
Diamond-cutting
is the most difficult due to its superior hardness. Diamond cutters
form an aristocracy among gem cutters. Those engaged in cutting stones
other than diamonds are known as gem cutters or lapidaries. The
principal diamond-cutting centres used to be in Belgium, Germany and
Holland. Antwerp in Belgium used to have the largest number of cutters,
about 20,000, Germany about 6,500 and Holland about 4,000. But after
the invasion of Holland and Belgium by Germany the cutting
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