Sodium, which we know as part of a mineral we call salt, is a very soft light grey metal. It will flare up in air and is never found as a metal naturally.So it may come as a surprise to find that it is the sixth most common element on Earth.

Sodium is essential to life, which is why we need to eat salt. The way it works is to be in the body, pulling nourishment out of the blood and into our body cells. Too much sodium may cause this to happen too much and that brings on high blood pressure.

The video shows a piece of salt from a salt lake.