What it is: The startup, which launched publicly in November, claims it can grow hundreds of diamonds that are up to nine carats in just two weeks in a lab. The company had been working for three years to come up with a way to lab-grow pure diamonds, not synthetics. The company says it discovered a plasma that allows atoms to attach themselves to the thin slice of Earth-extracted diamond. The atoms then stack on top of that natural diamond, layer by layer, until a pure, jewelry-grade diamond is formed.

Funding: Less than $100 million. Diamond Foundry has closed three rounds of financing from individuals including actor Leonardo DiCaprio, Twitter/Medium founder Evan Williams, Zynga founder Mark Pincus, One Kings Lane cofounder Alison Pincus, SUN Microsystems founder Andreas Bechtolsheim, Facebook cofounder Andrew McCollum, former Facebook COO Owen van Natta, Marc Benioff’s private-investment manager Mark Goldstein, David Spector, former eBay President Jeff Skoll, Scott Banister, Vast Ventures, Caspian VC Partners, and many others.

Website: https://www.diamondfoundry.com/