Native carbon in hexagonal crystals, also foliated or granular massive, of black color and metallic luster, and so soft as to leave a trace on paper. It is used for pencils (improperly called lead pencils), for crucibles, and as a lubricator, etc. Often called plumbago or black lead.
A form of carbon, used in pencils, stick, or powder form. Graphite can be measured in different variations of hardness, such as 9B to 9H. See the Drawing and Sketching forum.
The most stable allotrope, or form of carbon, having a hexagonal type linking of atoms with relatively strong bonds to 3 neighboring carbon atoms, and a much weaker bond to a fourth carbon atom.