Appearance
Iodine is a blue-black, shiny solid which sublimes at room temperature into a violet-blue gas with an irritating odour.

Source
Iodine occurs sparingly, 0.05 parts per million, in seawater. From this source it is assimilated by seaweeds, brines from old sea deposits and brackish waters from oil and salt wells.

Iodine is obtained commercially by extracting Iodine vapour from processed brine, by ion exchange of brine or by liberating Iodine from iodates obtained in nitrate ores.

Uses
Iodine is used in several areas including pharmaceuticals, photographic chemicals, printing inks and dyes, catalysts and animal feeds.

General Information
Iodine forms compounds with many elements, but is less active than the other Halogens. It dissolves readily in Chloroform, Carbon tetrachloride and Carbon disulphide to form beautiful purple solutions. It is only sparingly soluble in water. Organic Iodine compounds are important in organic chemistry

Iodine is an essential element, lack of which can cause thyroid gland problems. A solution of Potassium iodide and Iodine has germicidal effects and is used for the external treatment of wounds. Iodine can cause lesions when in contact with the skin, and Iodine vapour is extremely irritating to the eyes and mucous membranes.