Discovered in 1925, Rhenium was named after the German homeland waterway, the Rhine River. It is an extremely hard, silvery-white metal and almost twice the density of lead. Its melting point, 3170^oC, is among the highest of all the known elements.

Rhenium occurs naturally as an impurity in molybdenite (MoS₂) and to a lesser extent in copper sulfide ores. It is used in thermocouples alloys, and has numerous applications in elelctronic devices such as contact points of electrical switches. It can be electroplated, but its high cost limits its use to specialty items.