text: Pitch, a traditional naval store, was traditionally used to help caulk the seams of wooden sailing vessels (see shipbuilding).  Other important historic uses included coating earthenware vessels for the preservation of wine, waterproofing wooden containers, and making torches. Petroleum-derived pitch is black in colour, hence the adjectival phrase, "pitch-black".
  The viscoelastic properties of pitch make it well suited for the polishing of high-quality optical lenses and mirrors. In use, the pitch is formed into a lap or polishing surface, which is charged with iron oxide (Jewelers' rouge) or cerium oxide. The surface to be polished is pressed into the pitch, then rubbed against the surface so formed. The ability of pitch to flow, albeit slowly, keeps it in constant uniform contact with the optical surface.
  Chasers pitch is a combination of pitch and other substances, used in jewelry making.