Caribbean topaz is a specially treated type of topaz that is modified with a titanium undercoat in order to change the way in which light is captured by the gem, resulting in a swirl of blue and green hues. Caribbean topaz are not sourced from the Caribbean; instead, the name being instead a reference to their particular color scheme and its relation to the Caribbean climate.
Caribbean topaz start their lives as neutral topaz, white in color. They are then subjected to a patented process which covers part of the cut gem in an extremely thin layer of titanium. This radically alters the gem's color scheme by changing the refraction process.
A well-made Caribbean topaz can display almost any mixture of colors. The gems are often compared to rainbows for the way in which they refract a changing wash of colors depending on the light conditions and on how they are held up to said light.
Natural topaz come in a great variety of colors ranging from pink to brown. Caribbean topaz are manufactured as an answer to the colors missing from the gemstone's natural spectrum and as a way to repurpose otherwise drab white topaz. They are often used in jewelry like rings and bracelets to provide color.