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Indicolite
This is basically the blue variety of tourmaline,
but it r also be greenish blue or otherwise vary from the
inc. color suggested by its name.
Appearance Generally indicolite is quite
a deep b even the color of dark blue ink, perhaps appearing
greer one direction because of its strong pleochroism. Sor,
times indicolite is an overall greenish blue, which, un -
the color of greenish blue sapphire, is very attract Stones
are often clear and free of inclusions, but inte, pleochroism
may make them so dark in one direction a_ appear lacking in
transparency. This gem is given mix faceted and also rectangular,
step cuts. It generally good luster.
Distinctive features The greenish
blue color is unr takable and particularly attractive. Loss
of transparenc. one direction is another distinctive characteristic
anc: best seen in rectangular gems. Because of its apprecia.:
birefringence, if the stone is examined with a standard jeler's
10x lens, the opposite facet edges look double certain directions.
Mid-blue zircon, with three times birefringence, also shows
this effect, but to a far grea extent, and is a very different,
lighter color, with grer, luster.
Occurrence Indicolite is mainly found in
Brazil (state Minas Gerais), but also in the United States
(Colora Massachusetts, California), Namibia, Madagascar, and
Soviet Union (Urals).
Value Attractive, definite blue, bright blue
or blue-grestones are priced similarly to fine rubellites,
and are la common. But when the color is too deep, and inky
blue. ' value falls considerably, as it does with the less
attrac* rubellites.
Simulants and synthetics It is neither imitated
nor ~ duced synthetically.
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