what is a zirconium
If zirconia is a single crystal form, then it is the cubic zirconia gemstone that we discussed earlier. Lesson Summary. Zirconium is a metal that has 40 protons in its nucleus, so it is the 40th element on the periodic table. It has the chemical symbol Zr. It was discovered by Martin Heinrich Klaproth in 1789 and first isolated by JÃ¶ns Berzelius in 1824.