The Federal Trade Commission (FTC) requires the disclosure of any treatment done to a natural gemstone when it is non-permanent, or requires special care to retain the benefit of the enhancement, or if the treatment has a material effect on the value of the gemstone.

How should these treatments be communicated? Ask you dealer about the stone and the codes-

N = not enhanced

D = Dyeing

HP = Heat & Pressure

O = Oiling/Resin

SC = Special Care

ASBL = Assembled

B = Bleaching

F = Filing

I = Impregnation

R = Irradiation

W =Waxing/oiling in Opaque Stones

CMP = Composite

Ask a lot of questions before buying and make sure you have a disclosure.