About the element

Rhenium is a chemical element with the symbol Re and atomic number 75. It is a silvery-gray, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion, rhenium is one of the rarest elements in the Earth’s crust.


Key facts

Most of the targeted by-products elements are Critical Raw Materials (CRMs). CRMs combine raw materials of high importance to the EU economy and of high risk associated with their supply.

  • Symbol: Re
  • Atomic number: 75
  • Atomic mass: 186.207 u
  • Melting point: 3,185 °C