Iodine is a chemical element with symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a lustrous, purple-black metallic solid at standard conditions that sublimes readily to form a violet gas.

Atomic Weight:  4545
Density:        12.67 g/cm3
Melting Point:  5237 °C
 Boiling Point: 6767 °C