Antimony (Sb)

NUM: 51
SYMBOL: Sb
CATEGORY: Metalloid

Antimony is a lustrous gray metalloid found in nature mainly as the sulfide mineral stibnite.

Antimony compounds have been used since antiquity, with the sulfide mineral stibnite serving as kohl eye cosmetic in ancient Egypt.
It is a brittle metalloid that, unusually, expands slightly as it solidifies, which made it valuable in sharply cast printing type.
Antimony trioxide is a major flame-retardant synergist, and the metal hardens the lead grids of lead-acid batteries.