Rhodium has a cool-gray colour and is known to be extremely hard and corrosion resistant.

Like its sister metals platinum and palladium, rhodium also has excellent catalytic activity. Many complex chemical compounds have been developed for use as catalysts, especially in the organic chemicals industry. Rhodium-platinum gauzes are used in the production of nitric acid.

In vehicle exhaust emission control, catalysts containing rhodium are of major importance on account of their exceptional activity and selectivity. Today's three-way catalyst for gasoline engines uses rhodium to catalyse the reduction of nitrogen oxides to nitrogen.

Rhodium's high melting point, high temperature stability and corrosion resistance makes it key to many industrial processes such as glass and glass fibre production. Rhodium's hardness makes it an excellent alloying agent to harden platinum.