Antimony is a chemical element with the symbol Sb and atomic number 51. It is a silvery-white metal that is brittle and can break easily. Antimony is often used in alloys to improve their strength and durability, making it valuable in industries like electronics and batteries. In nature, antimony is usually found in the form of stibnite, a mineral that contains antimony sulfide. This element has been known since ancient times and was used in cosmetics and medicine. Today, antimony plays a crucial role in flame retardants, helping to make materials safer from fire hazards.