This also means the platinum group metals may be soldered without the use of fluxes. The higher melting point of platinum requires an oxygen-fuel style torch for soldering and casting. Palladium is used in alloys with gold or platinum in expensive jewelry. Rhodium, a metal in the platinum group, is often used for plating over white gold to add toughness. It has a highly reflective surface, second only to silver.
Iridium is added to platinum to add even further toughness.
Osmium, plated onto manufactured goods, adds wear resistance to contact surfaces. Blue Ocean Jewellery Limited .