BERYLLIUM (BE)

formerly (until 1957) glucinium, chemical element, one of the alkaline-earth metals of Group IIa of the periodic table, used in metallurgy as a hardening agent and in many space and nuclear applications. Beryllium was discovered (1798) as the oxide by Nicolas-Louis Vauquelin in beryl and in emeralds, and was isolated (1828) as the metal independently by Friedrich Whler and A.-A.-B. Bussy by the reduction of its chloride with potassium.