graphite
n. uncountablen. a soft, black mineral that is a form of carbon. You most often find it inside pencils as the 'lead' you use for writing or drawing.
n. a naturally occurring, soft, greyish-black crystalline form of carbon. It is used as a dry lubricant, in nuclear reactors, and as the writing core in pencils.
The artist uses graphite to create soft shadows in her drawings.
Pencil manufacturers mix graphite with clay to determine the hardness and darkness of the writing core.
Due to its high thermal conductivity and chemical stability, graphite is an essential component in the manufacturing of electrodes and high-temperature crucibles.
Borrowed from German Graphit (A. G. Werner 1789), from Ancient Greek γράφω (gráphō, “I write”).
Uncountable when referring to the mineral substance; occasionally countable when referring to specific artistic tools or industrial grades.