The US Federal Trade Commission, which investigates allegations of deceptive advertising, has sent warning letters to eight companies to insist they distinguish in advertisements between diamonds from mines and those made in laboratories.
The FTC said it had found instances where the eight companies advertised diamond jewellery “without clearly and conspicuously disclosing that the diamonds are laboratory-created,” according to the letter.
Analysts say increased production of laboratory-grown diamonds has lowered their price. The Diamond Producers Association (DPA), which represents mining companies including De Beers, Rio Tinto and Alrosa, welcomed the FTC insistence.