Lithium’s most common uses include in the creation of batteries and its use in medication. Lithium is a very reactive metal and unlike a lot of metals it can be cut with a knife. It reacts violently with water and if left out in air it will react with oxygen by the process of oxidation. Lithium very often has to be kept in oil for storage to prevent it reacting with moisture and oxygen in the air. Lithium is a metal in Group 1 of the period tables. It is a solid at room temperature and it has a melting point of 1330°c and a boiling point of 180°c. Lithium was discovered in 1817 by the Swedish scientist Johan August Arfvedson through his analysis of the mineral Petalite. As Lithium is so reactive it does not occur freely in nature, however it is found as an ore. In 1855, the British chemist Augustus Matthiessen managed to purify Lithium from Lithium Chloride. Lithium is a metal with the lowest known density and will easily float on water.