GIA gemstone certification analyzes and identifies treatments in colored gemstones such as Sapphires and other precious gemstones like Pearls. Colored gemstones like Sapphires are tested for traces of heating, irradiation, fracture-filling, clarity enhancement, coating, dyeing, and diffusion. Whereas, Pearls are examined for bleaching, heating, dyeing, irradiation, coating, skinning, filling, and impregnation.