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Green tourmaline
This color variety of tourmaline has no separate
name, bw is as well-known as rubellite and indicolite.
Appearance Green-colored tourmaline
comes in a widF range of different shades, so, at first sight,
many greer tourmalines may look very similar to other gems.
Shade, may include the yellowish-green of some olivines, or
thr stronger, deeper green of others; a lightish paintbox
green like some zircons, is also possible as is a stronger
versior of this color, like some African emeralds. Tourmaline
car be a brilliant green, a touch colder than the color of
emerald (this is typical of tourmaline); or leaf green, tending
tc deep olive green (also very typical and known, in fact,
a~ tourmaline green). If they are large, green tourmalines
ara given either a step cut (not always with truncated corners
or a pear-shaped or oval mixed cut. If the stones are small
they are most often given a round or roundish oval cut Mid-
to light-colored specimens have good luster. Darke, stones
often look a bit opaque. Many are virtually free c - inclusions.
Distinctive features The more definite or
darker shade~ are characteristic. Loss of transparency along
the stone particularly in gems that are cut rectangularly,
is peculiar tc tourmaline. Mid-green stones that are given
a rectangular cut often show alternate longitudinal lines
of lighter anc darker color because of the way in which light
is reflectec from the pavilion facets. This optical effect
is unique anc therefore distinctive. But when the color is
similar to that e* other gems, the identity of the stones
can only be distinguished by measurement of physical characteristics
sucr as density and refractive indices.
Occurrence Green tourmaline is found in Brazil,
the United States (Maine), Tanzania, Mozambique, and Namibia.
It is also extracted in the Soviet Union and from the gem
gravels of Sri Lanka, where the lighter stones, somewhat like
olivine, are the most common. It is quite plentiful and widespread.
Value As with rubellite and indicolite, only
the lively mid-colored stones are valuable. When the color
is an uncharacteristic pale green, or the most typical dark
or olive green, they are worth much less.
Simulants and synthetics It is neither imitated
nor produced synthetically.
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