Mineral Black

An earth pigment: a soft, clay-like carbonaceous shale of carbon with alumina and silica, ground to a dense non-reflective black. Worked in Britain almost exclusively in north Devon, where it was sold as Bideford Black or Biddiblack, and used in ships’ paint, camouflage, rubber, paper, pencils and cosmetics until synthetic carbon blacks displaced it in the 1960s.