Rado DiaStar Original - in the "mythical" XL Size nobody could ever find
Had to special order it from Rado in Switzerland in 2007; it was the only way to get one in the U.S.
Their DiaStar is the model that made Rado its name in 1962 with "scratchproof" materials. The crystal is faceted sapphire and the case shell is sintered tungsten carbide. Rado has since differentiated themselves with high tech ceramics, diamond coatings, and other materials that defy being scratched.