The International Gemological Institute (IGI) India has urged diamond buyers to go only for certified products amid concerns over synthetic diamonds being sold as real ones. One should not be buying diamond blindly. There are concerns and that is why we are advising people to buy only certified diamond jewellery, said Tehmasp Printer. It said certification eliminated fakes and enabled the buyer to know the exact quality of genuine diamond. IGI India officials said of all the diamond jewellery sold in India, up to 60% were certified, leaving the rest 40% to uncertainties.