Ruthenium is a chemical element with symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most other chemicals
R 5991 (OTTO) Ruthenium foil, 1.5 mm thick, 99.9% Cas 7440-18-8 - used as an alloying element with platinum and palladium to produce alloys which have improved wear resistance, and with titanium to improve the material's corrosion resistance.