About Tungsten Rings: Tungsten rings are composed of a metal alloy, tungsten carbide. The alloy allows for maximum hardness and rigidity without sacrificing tensile strength. Each tungsten carbide ring is cut and polished with diamond tools. Tungsten rings are not sizable by ordinary jewelers' tools -- the metal is too hard. Most tungsten metal powder is converted to tungsten carbide (WC) by reaction with pure carbon powder, e.g. carbon black, at 900 - 2200°C in pusher or batch furnaces, a process called carburisation.