The element carbon, in the form of graphite, is used in lead pencils. Interestingly enough, diamond is another form of carbon.
The element used in the 'lead' pencils is not actually lead but carbon, in the form of graphite.
graphite
The lead in pencils is made of the element carbon, in the form of graphite. Graphite powder is mixed with clay and wax. The more graphite the pencil contains, the softer the lead, and darker the mark.
Graphite.