Lithium

Lithium is the third element in the elemental table. Lithium is not found free in nature, though it can be found as a mineral within rocks. Lithium metal burns white, though when held up to a flame turns crimson. Lithium is about half the weight of water, which means that if it didn't react with water (which it does), it would float. It is known as the lightest metal on earth.

Lithium is often used in medicine, as a heat transfer agent, and in batteries among other uses. The transmutation of lithium to tritium was the first ever manmade nuclear fusion reaction. The medical purposes of lithium are known to be good for treating mania and deep depression. Also, in 1949, a doctor name John Cade discovered that the lithium he had found could be used to treat bipolar people. 

So where does lithium come from?

Lithium structure

Lithium can not be found free in nature, as mentioned above, but can be found as a mineral in rocks and in mineral water. That is how it's medicinal purposes were discovered; by giving the patients water with lithium in it. Lithium traces can also be found on plankton and various plants.

 Lithium can kill algae and absorbs carbon dioxide, even in space. Lithium is also used in batteries, and most recently used in a battery study that is working to produce a battery that is the same size as normal, but has ten times the storage space. Northwestern University workers predict that this technology will be available in 3-5 years.