Carbon is so interesting. It is found in its humble form of coal and its coveted form of diamonds. Allotropes present the collector of elements with a choice as they have to pick one or the other or shoehorn two or more types into the slot. In the "humble" form carbon has several further sub-choices and you can pick any color as long as it's black! Amorphous, crystalline, glassy and nanotubes can all be selected as representing the sixth element on the periodic table.