Copying pencil the wound. Such risks are not associated with ordinary graphite pencils. While these symptoms may appear after a couple of days they often develop only after weeks have passed since the injury was sustained. Surgery is required to remove the dye and the infected tissue and "the necrotizing action may be so severe and extensive amputation is necessary". Copying pencil A copying pencil, also indelible pencil or chemical pencil, is pencil whose lead contains a dye. The lead is fabricated by adding a dry water-soluble permanent dye to powdered graphite—used in standard graphite pencils—before binding the mixture with clay. Copying
Negro (lead pencil) what they call Nero pencils, which are similar in composition. Prismacolor also manufactures a lead-based black pencil that is very close in composition. Negro (lead pencil) Negro is the name of an artist's drawing medium, consisting of black pencil lead often encased in a wooden or paper tool. Its history and uses are common knowledge among illustrators and historians interested in illustrative art. The word "Negro", translates to "black" in Spanish and Italian, and is a term commonly used to describe artists' media and pigments that are black or dark in color. Negro lead was originally composed of a mixture