This color variety of tourmaline has no separate name, but is as well-known as rubellite and indicolite.
Appearance Green—colored tourmaline comes in a wide range of different shades, so, at ﬁrst sight, many green tourmalines may look very similar to other gems. Shades: may include the yellowish-green of some olivines, or the stronger, deeper green of others; a lightish paintbox green, like some zircons, is also possible as is a stronger version of this color, like some African emeralds. Tourmaline can be a brilliant green, a touch colder than the color of emerald (this is typical of tourmaline); or leaf green, tending to deep olive green (also very typical and known, in tact, as tourmaline green). If they are large, green tourmalines are 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. Darker stones often look a bit opaque. Many are virtually free of inclusions.
Distinctive features The more definite or darker shades are characteristic. Loss of transparency along the store, particularly in gems that are out rectangularly, is peculiar to tourmaline. Mid-green stones that are given a rectangular out often show alternate longitudinal lines of lighter and darker color because of the way in which light is reflected from the pavilion facets. This optical effect is unique and therefore distinctive. But when the color is similar to that of other gems, the identity of the stones can only be distinguished by measurement of physical characteristics such as density and refractive indices.
Occurrence Green tourmaline is found in Brazil, the United States (Maine), Tanzania, Mozambique, and Namlibia. It is also extracted in the Soviet Union and from the gem gravels of Sri Lanka, where the lighter stones, some what 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 lt is neither imitated nor produced synthetically.