This is the name now given to the violet variety of corundum. lt 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. lt 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. lt is accorded much the same value as other, secondary gemstones, being some what 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.