Carbon Carbon, an element discovered before history itself, is one of the most abundant elements in the universe. It can be found in the sun, the stars, comets, and the atmospheres of most planets.
Carbon occurs in many forms in nature.
One of its purest forms is diamond. Diamond is the hardest substance known on earth. Although diamonds found in nature are colorless and transparent, when combined with other elements its color can range from pastels to black. Diamond is a poor conductor of heat and electricity. Until 1955 the only sources of diamond were found in deposits of volcanic origin.