Rhodium: You're Covered

While the majority of the world’s rhodium production is used mainly for catalytic converters, its mighty durability makes it a fantastic plating aid that helps fine metals achieve a white and highly reflective finish.

Rhodium is a member of the platinum group and a noble metal. Metals in the noble family share similar characteristics, such as being hypoallergenic and highly resistant to wear, tarnishing, and corrosion. Those qualities make rhodium ideal for jewelry. However, you’ll never see it made into a solid piece of jewelry because its extremely brittle and comes with a high price tag.

Fun Fact: When no other metal was sufficiently fine enough to say, “congratulations,” the Guinness Book of World Records presented Paul McCartney with a rhodium-plated disc for his achievement as being the best-selling songwriter and recording artist of all time in 1979.

Rhodium is one of the most rare and valuable elements in the world. The Earth’s crust only contains an estimated 0.0002 parts per million. It’s a by-product of platinum mining and only mined in conjunction with platinum’s demand, which contributes to its notorious price swings. When more rhodium is needed than can be mined from platinum’s current demand, the price goes up.

Jewelers apply rhodium to jewelry via electroplating, which is the process of coating of one metal with another by electrolytic deposition. White gold is often plated with rhodium to improve its appearance and color. Silver is also plated with rhodium to help hinder tarnishing.

It’s normal to see the plating wear over time because of contact and interactions with surfaces, requiring the jewelry to be plated again. Fortunately re-plating is a simple process.