And apparently they've kept it a secret since the 1970s. I wonder how DeBeers feels about this?
Russia reveals shiny state secret: It's awash in diamonds
'Trillions of carats' lie below a 35-million-year-old, 62-mile-diameter asteroid crater in eastern Siberia known as Popigai Astroblem. The Russians have known about the site since the 1970s.