See more Zirconium products. Zirconium (atomic symbol: Zr, atomic number: 40) is a Block D, Group 4, Period 5 element with an atomic weight of 91.224. Zirconium Bohr ModelThe number of electrons in each of Zirconium's shells is 2, 8, 18, 10, 2 and its electron configuration is [Kr] 4d2 5s2. The zirconium atom has a radius of 160 pm and a Van der Waals radius of 186 pm. Zirconium was discovered by Martin Heinrich Klaproth in 1789 and first isolated by Jöns Jakob Berzelius in 1824. In its elemental form, zirconium has a silvery white appearance that is similar to titanium. Zirconium's principal mineral is zircon (zirconium silicate). Elemental ZirconiumZirconium is commercially produced as a byproduct of titanium and tin mining and has many applications as a opacifier and a refractory material. It is not found in nature as a free element. The name of zirconium comes from the mineral zircon, the most important source of zirconium, and from the Persian wordzargun, meaning gold-like.