Pure carbon, C; sp. gr. 2.1; hardness 2; greyish-black; feels soft and greasy; good basal cleavage; scaly, columnar, granular, or earthy; occurs in veins and may be disseminated through rocks as a result of metamorphism of original carbon-rich sediments. It is used as a lubricant, electrical conductor, and in the manufacture of crucibles and paint.