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 1769 (OTTO) Ruthenium pellets, 3-6 mm, 99.95% Cas 7440-18-8 - used to make electrical contacts for resistance to severe wear.