Hafnium Element Cube

Hafnium is a chemical element with the symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals. Hafnium is mostly used to make control rods for nuclear reactors. When hafnium is alloyed with other metals it increases protective coating adherence. This is why it was used in thruster nozzles of the Apollo lunar modules.