a rare polyvalent metallic element of the platinum group; it is found associated with platinum
A hard, brittle, grayish-white rare earth metal with an atomic symbol Ru, atomic number 44, and atomic weight 101.07. It is used as a catalyst and hardener for PLATINUM and PALLADIUM.
A steel gray metallic element. It oxidizes on prolonged exposure to the air, but is scarcely affected by the action of any acids. Symbol, Ru. Atomic weight, 102.