Rhodium is a chemical element; it has symbol Rh and atomic number 45. It is a very rare, silvery-white, hard, corrosion-resistant transition metal. It is a noble metal and a member of the platinum group. It has only one naturally occurring isotope, which is 103Rh.
It reduces nitrogen oxides in exhaust gases. Rhodium is also used as catalysts in the chemical industry, for making nitric acid, acetic acid and hydrogenation reactions. It is used to coat optic fibres and optical mirrors, and for crucibles, thermocouple elements and headlight reflectors.
Rhodium is a member of the platinum group of metals and is silver-hued, highly reflective and does not tarnish or corrode. It is harder than gold and is highly durable. If you see the stamp, and the ring is silver-colored, it's rhodium-plated.
Rhodium, a rare and valuable metal, was discovered in 1803 by English chemist William Hyde Wollaston. He obtained it from a sample of platinum ore that originated in South America. While trying to purify platinum, Wollaston noticed a red residue that remained after various chemical treatments. This residue turned out to be a compound containing rhodium.
Wollaston named the new element "rhodium" after the Greek word for "rose," referring to the rose-red color of some of its compounds. For many years, rhodium had limited uses due to its rarity. However, its unique properties, such as high resistance to corrosion and excellent catalytic abilities, eventually led to its widespread application in various fields.