De Beers’ Confidence Game With increasing reports of synthetic diamonds being passed off as natural, De Beers has warned its 82 sightholders that selling lab-grown diamonds without noting their origin “threatens consumer confidence” and “may be a criminal offense.” De Beers also sent its clients info on its Automated Melee Screening device, which is being sold by the De Beers-owned International Institute of Diamond Grading and Research. The machine screens stones as small as 0.01 ct. to 0.2 ct. and can screen an average of up to 360 stones per hour. While the machine can detect if a stone is non-natural, it does not screen for treated stones, De Beers said. Sightholders must pay $25,000 per year to lease the device, totaling $75,000 over three years. Deliveries will start in March 2014. The company seemed to dismiss demand for lab-grown diamonds on a consumer level.