Element number 85, the heaviest naturally occurring halogen. It is one of the most unstable elements in nature, with its longest half-life at only just over 8 hours, so much so that at any given time less than a gram is believed to exist in the entire Earth, making it also one of the rarest naturally occurring elements. Most notably, it is the only element which requires one to say both "ass" and "tit" in its name.

A highly unstable radioactive element, the heaviest of the halogen series, that resembles iodine in solution. Its longest lived isotope has a mass number of 210 and has a half-life of 8.3 hours.