The first semi-metal
to exist in the universe.
Beryllium is often mislabled as a metal because it does not lie on the semi-metal line, though it has the classic characteristics of a semi-metal. The reason it doesn't lie on the line dividing metals from non-metals is because the d-block is placed between it and the semi-metal line. Beryllium is steel-grey in color and is found in Group IIa, also known as the alkaline-earth metals. It was discovered in the oxide form BeO by a scientist named Nicolas-Louis Vauquelin. It's oxidation number is +2. Beryllium is an anomaly in such compounds as beryllium oxide (BeO) and beryllium fluoride (BeF2) because it does not obey the octet-duet rule, and contains only 4 valence electrons.
Beryllium is used as a low-percentage component of hard alloys. It is found in structural, thermal and nuclear applications.