Diamond is an allotrope of carbon. High temperature and extreme pressure on carbon atoms cause them to crystallize over a long-time and they are formed beneath the earth surface. The stone, thus formed are pushed through to the earth surface by means of volcanic eruption through pipes known as kimberlitic. They can also be found at the bottom of rivers. Diamonds are found in various colors like white, green, blue, pink, red, black and so on. The diamond has very good mechanical and optical properties.
