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Peridot, Olivine, or Chrysolite
This stone has been known for a very long time.
The ancients (including Pliny the Elder) spoke of a gem called
topazos (corresponding to our word topaz) which, from the
description, appears to be olivine. This gem was called topazos
because it came from an island in the Red Sea named Topazos,
now known as Zebirget, a fact which tends to confirm that
it was indeed olivine. This is obviously one of those cases
in which an old gem name has survived but has subsequently
become attached to a different gem.
Appearance Typically olive
green, olivine can be a strong, almost bottle green, or yellowish
green. In the gem trade, the greener type tends to be called
peridot, and the yellower type chrysolite. It has vitreous
luster. Stones are usually transparent, with few inclusions
and are given ali types of mixed cuts, oval, round and pear-shaped,
plus rectangular and square, step cuts. Gems of several carats
are often seen, but very large stones are hardly ever found
Small stones are also cut and arranged in intricate patterns
in jewelry.
Distinctive features The particular color
and luster are highly characteristic, although some tourmalines,
zircons, and chrysoberyls may look much the same. A quick
way of distinguishing them is by testing the density. Chrysoberyi
and olivine also have very different refractive indices and
chrysoberyl is usually more lustrous.
Occurrence The island of Zebirget still supplies excel
lent olivines, as it did in antiquity. Others come from the
United States (Arizona), the Hawaiian islands, Burma, and
Brazil.
Value Much appreciated in the past, olivine
is the victim of changing fashions and is far less highly
prized today Even exceptionally fine, large stones do not
fetch very high prices and smaller ones are very low-priced.
Simulants and synthetics Olivine has been
imitated by appropriately colored glass, synthetic corundum
and synthetic spinel. It has also been synthesized experimentally
but its low value has discouraged such attempts.
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