Rhodium is an inert chemical element that is hard and silvery white. It is highly resistant to corrosion and this, combined with its attractive luster makes it an ideal metal for electroplating in jewelry. It's also used in electrical contacts, optical equipment, and as a filter in mammography scans. It's also been used in catalytic converters. In itself, the stuff is not dangerous, being inert. However, rhodium complexes can kill rats if they're dosed at about 200 mg of rhodium chloride. The stuff will also leave one hell of a stain if you get it out of that inert state. Apart from that, though, this stuff is pretty safe on its own and hellaciously useful. Hope that helps.