Antimony

Antimony is a brittle, silvery-blue metalloid known since ancient times; its sulfide mineral, stibnite, was ground into black eye makeup in ancient Egypt. Its symbol, Sb, comes from stibium, its Latin name. Most antimony today is mined in China, Russia and Tajikistan.

Its largest use is in flame retardants, where antimony oxide boosts the fire-stopping power of halogen compounds in plastics, fabrics and electronics. It also hardens the lead in car batteries and is the most common catalyst for making PET (polyester) plastic, used in bottles and in many of the films inside the television's backlight. Some semiconductors and infrared detectors use it as well.