Some gemstones are routinely treated, and the treatment is well known and accepted in the gem and jewellery industry. However, there are some treatments that are not routinely done and must be disclosed to the buyer by the seller. The common treatments that must be disclosed by the seller include glass filling, oiling, resin filling, flux filling, dye, smoke, and sugar treatments, diffusion treatments and in some cases irradiation. Failure to do so is against the worldwide industry code of ethics and regarded as fraud. Why is this important? These treatments can significantly negative influence on the value of the gem. Click here to read full article Treatment of gemstones