International Gemstone Treatment Codes

There are two organizations with gemstone treatment codes for disclosure of treatments common in the gem and jewellery industry. The CIBJO and the AGTA below is a list of the codes used for assuring the integrity of the gems sales and giving the retail public a means of making informed educated decisions.

  • N = NOT ENHANCED
  • F = FILLING
  • O = OILING/RESIN
  • H = HEATING
  • R = IRRADIATION
  • B = BLEACHING
  • U = DIFFUSION
  • C = COATING
  • L = LASERING
  • HP = HEAT & PRESSURE
  • D = DYEING
  • I = IMPREGNATING
  • SC = SPECIAL CARE
  • W = WAXING/OILING REQUIRED IN OPAQUE STONES