Tourmaline heat treatment

Hi I have a very dark blue tourmaline and a very dark chrome
tourmaline. If their color was a little bit lighter, these
stones would surely be terrific. Does anybody know if heat
treatment would help ? If yes, could you tell me how to heat
treat them ? Thanks

Claude Marc-Aurle

Hello Claude,

Heat treatment on tourmaline will usually lighten the color.

At about 700 C the darker green stones will lighten in color to
a medium emerald green, but the pink tourmalines will become
colorless.

Best regards,

Francoise.