Atomic Number:	85
Atomic Symbol:	At
Atomic Weight:	210
Electron Configuration:	[Xe]6s24f145d106p5

Astatine is radioactive and essentially unavailable in nature. It is not possible to make other than in a nuclear reactor. Astatine is a halogen and possibly accumulates in the thyroid like iodine.

The "time of flight" mass spectrometer has been used to confirm that this highly radioactive halogen behaves chemically very much like other halogens, particularly iodine. Astatine is said to be more metallic than iodine, and, like iodine, it probably accumulates in the thyroid gland. Workers at the Brookhaven National Laboratory have recently used reactive scattering in crossed molecular beams to identify and measure elementary reactions involving astatine.