Mystic Topaz is quite new, first seen around 1998.
It is natural colorless (white) Topaz that has been coated, giving it a unique rainbow color effect. Therefore, it is not a gem type, but is an enhanced clear Topaz.
Mystic Topaz may be so-called because its attractive changing colors appear deep, mysterious and unusual. Mystic topaz usually appears to display rainbow colors, with greens, blues and purples being quite prominent.
Since the treatment is a coating, it is not a permanent enhancement, but its remarkable appearance makes it an interesting gem in its own right.
Mystic topaz has also been called “fire topaz”, “mystic fire topaz”, “Alaska topaz”, “Alaskan ice”, “Caribbean topaz” and “rainbow topaz”.