Topaz

The main topaz deposits are in Brazil, but very nice topazes can also be found in Madagascar, Myanmar, Mexico, Nigeria, Pakistan, Russia, Sri Lanka and Zimbabwe.

-Heat treatment: most pink topazes are actually heated yellow topazes.

-Irradiation: artificial irradiation will completely change the colour of a topaz to very attractive green, orange, pink or intense yellow shades.

The resulting color is not stable and fades upon exposure to light.

-Irradiation followed by annealing (heat-treatment to stabilise the resulting colour):

most blue topazes on the market are actually very pale blue gemstones turned into “swiss blue” or “london blue” thanks to this stable treatment.

– Diffusion: a stable treatment that turns average pale topazes into attractive green ones.

– Coating: some colorless or very pale topazes can be coated with metal oxides to create the appearance of very colourful gems, or a special effect like in a “mystic” topaz.

– Do not leave the topaz under a strong light as the colour may fade.

– Working on topaz requires lots of care as its cleavage can be tricky.

– Be very careful when using ultrasound and steam jets

– Thermal shocks should be avoided

– Impacts should also be avoided as it might break the stone

– Keep away from acidic substances as well.