Rare and precious, platinum is a bright white metal that is also durable and hypoallergenic.
Platinum was a popular metal for jewelry until the early 20th century, when it was taken off the market for military use during wartime. Platinum is extremely durable. It's shiny and beautiful, but it's also a metal that will last for generations. Since the late 1990s, platinum has returned as a top choice for engagement rings and other jewelry.
When used in jewelry, it is usually is mixed with other similar metals, known as the platinum group metals: iridium, palladium, ruthenium, rhodium and osmium. However, for a piece of jewelry to be labeled as "platinum" it must have a minimum level of purity of at least 90% pure platinum. A purity level of less than 90% would require the metal be identified as a platinum alloy. Platinum jewelry pieces can be identified by the hallmark "PLAT" stamped on the inside of the shank (rings) or the back of the piece.
Platinum has a soft white hue. It's 30 times rarer than gold (which means it's more expensive), 40% heavier than 14K gold and platinum will not tarnish or oxidize, however it ages beautifully by developing a lustrous patina. Because it is so strong and hard, the details of intricately engraved or embellished rings often look sharper and more precise. The bright whiteness of the metal makes it perfect for showing off diamonds and gemstones.