High-end jewelers are traditionally at the tail end of the diamond supply chain. Once they’re extracted, rough stones are typically acquired by specialist diamond cutters and polishers, who analyze each stone — sometimes for up to a year — to determine the ideal cut in which to shape them. Only after this process are the polished gems usually presented to high jewelry houses, who set them into glittering creations. But now a handful of houses are keen to master all stages of a stone’s journey from rough to final jewel. Last month, for example, British luxury jewelers Graff Diamonds bought the uncut Lesedi La Rona, the world’s second largest diamond, for $53 million.