A hard silver-white acid-resistant metallic element that is found in platinum ores and is used to harden platinum and palladium for jewelry and in alloys for nonmagnetic wear-resistant instrument pivots and electrical contacts. Atomic number 44; atomic weight 101.07; melting point 2,334°C; boiling point 4,150°C; specific gravity 12.1 (20°C); valence 0, 1, 2, 3, 4, 5, 6, 7, 8. See Periodic Table.