Cat's Eye Tourmaline

Cat's eye tourmaline displays chatoyancy which is caused by parallel inclusions consisting of fairly large hollow tubes. Because the hollow tubes are relatively big in diameter they cause the cat's eye effect which is more coarse and less focused than the one in chrysoberyl.

The most common colours are: pink, red, green, blue, greenish blue, occasionally bicolor.
General Information
A variety or type of:Tourmaline
Cat's Eye Tourmaline Treatments
Occasionally treated with acid to remove unsightly inclusions or dark staining in hollow tubes, they are then filled with lighter material. Sometimes hollow channels are filled with epoxy resin, this treatment can be undone by heating. - GIA 2019
Further Information
Mineral information:Cat's Eye Tourmaline information at
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