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Violet sapphire
This is the name now given to the violet variety
of corundum. It was formerly known as oriental amethyst,"
on account of its color; but this name has now been abandoned
in favor of the debatable, but mineralogically more precise,
term used for all minor forms of corundum.
Appearance The typical color
is a definite violet, like amethyst, which is very attractive
and tends to turn reddish violet in the sun or bright light.
But all gradations of color are possible from the violet blue
of some sapphires to the violet red of some rubies and the
violet pink of some pink sapphires. Whatever the exact shade,
it is always a very pleasing color, and has perhaps been less
appreciated than it deserves because of the association of
violet with mourning and sorrow in the West. As always with
corundum, it has very good luster, most evident in lighter
gemstones. It is usually given a mixed, oval cut. Stones weighing
a few carats are often found, but those of 10 carats and more
are rare.
Distinctive features When the
color of the sapphire tends to be blue-violet, red-violet
or pink-violet (the first turning more violet, the others,
redder, in sunshine or bright light), it is fairly distinctive,
but not so when it is a true violet or violet with a slight
hint of red. Some very fine amethysts look very similar to
such sapphires, even to the reddish tinge. The characteristic
luster of corundum is another distinctive feature, but here
too, care is needed, as amethyst can bear a close resemblance.
Violet sapphires are easily distinguished, however,
by their physical characteristics. If the density is measured
with a heavy liquid such as methylene iodide, corundum rapidly
sinks, while amethystine quartz floats.
Occurrence Many violet sapphires,
particularly the paler, pinker ones, come from Sri Lanka.
Much smaller quantities are also found in Thailand and Burma.
Value Despite its considerable
aesthetic qualities, violet sapphire is not widely appreciated.
It is accorded much the same value as other, secondary gemstones,
being somewhat more valuable than yellow sapphire (which is
more plentiful).
Simulants and synthetics Violet sapphire
does not appear to have been imitated; but from the time synthetic
corundum was first produced, various shades of violet have
been manufactured, along with the other varieties. Large quantities
of violet synthetic corundum are still produced, faceted into
every imaginable shape, from oval or round mixed cuts to true
brilliants and square and rectangular step cuts. The curious
thing is that these stones, which are often of considerable
size and weight (even 10 to 20 carats) are sold throughout
the world under the name of alexandrite, an extremely rare
form of green chrysoberyl that changes color to red, and is
therefore not even vaguely like synthetic corundum.
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