Disrupting De Beers

Diamond Foundry is using plasma reactors to turn tiny shards of diamond into gemstones. In doing so, the San Francisco company is taking on a deeply entrenched industry. 

- Sheila Marikar

A FEW MILES NORTH of San Francisco International Airport sits a squat, grey building just like a lot of other squat, grey buildings, except that this one contains a room full of machines growing billions of dollars’ worth of diamonds. Its facade is unmarked. “We don’t want to attract trouble, you know?” says R. Martin Roscheisen, a founder of Diamond Foundry, over Japanese takeout at his headquarters. He opens his mouth wide to offer a resonant laugh that sounds like the noise karate champions make while kicking through a piece of wood: “Hi-yah! Hi-yah! Hi-yah!”