Platinum is extremely dense, and is much more heavier than silver or gold. This property of platinum enhances the quality of the jewelry from which it is created. Platinum's ultimate stability platinum over the years is unmatched and it does not wear, and its remarkably high level of durability offers a profound guarantee of strength and longevity. Pure platinum is very malleable. We add different metals to platinum to harden the platinum.
Iridium is added to add even further toughness.
Iridium is more expensive than ruthenium. Iridium is harder than ruthenium. White gold is an alloy of gold and some white metals such as nickel, silver and palladium. White gold can be 18k, 14k, 9k or any karat. Platinum is not susceptible to problems like stress corrosion or stress cracking as can be the case with white gold.