Platinum is one of few high quality metals with a naturally white luster. It is also one of the only metals that can be used in almost its pure form (90%-95%) and does not tarnish as easily as white gold. Since it can be used in such a pure state, platinum is naturally hypoallergenic, making it an ideal choice for those with sensitive skin. Renowned for its superior durability, platinum will not wear away over time and will not change shape the way many other metals will. This strength, however, does not mean that platinum does not scratch. The metal scratches easily and commonly develops a natural patina over a number of years. This scratching, however, does not remove metal from the ring and a platinum ring will not thin over time the way a gold ring will. Found in very few mines throughout the world, platinum is 30 times rarer than gold and one of the rarest metals on the planet. A high melting point and difficulty with extraction and refining add to the rarity of the metal.