While lab-grown diamonds are starting to change the world of diamonds recently, the first artificial diamond was created in the 1950s, more than seventy years ago. No one knows how long it takes diamonds to form underground as mined diamonds are ancient, probably billion years old. Some graphite forms from the metamorphism of coal seams. He found that at about 4,150 C (7,500 F) the silicon in the carborundum vaporized, leaving the carbon behind in graphitic form. 12. Sprinter 4x4 Camper, Subscribe to our newsletter to recieve When they bond tetrahedrally, they create rigid three-dimensional crystals of unmatched hardness. /* Ned Stark Rebuilds The North Fanfiction, Police Officer Obituary, Articles OTHER