Mineral pitch, Jews' pitch, or compact native bitumen. It is brittle, of a black or brown color and high luster on a surface of fracture; it melts and burns when heated, leaving no residue. It occurs on the surface and shores of the Dead Sea, which is therefore called Asphaltites, or the Asphaltic Lake. It is found also in many parts of Asia, Europe, and America. See Bitumen.
A composition of bitumen, pitch, lime, and gravel, used for forming pavements, and as a water-proof cement for bridges, roofs, etc.; asphaltic cement. Artificial asphalt is prepared from coal tar, lime, sand, etc.
Tar product used as an acid resist in etching and inking base in lithography.
Naturally occurring gluey tar used by the Chumash for waterproofing canoes and baskets.
Same as Asphalt - Any of the natural bitumens and asphalts (brown or black) or the artificial pitches, except those produced by destructive distillation. Asphalt is also obtained from the residue of petroleum, coal tar, lignite, and tar.
Pitch, bitumen of Judea. An aquatint screen is made by allowing a deposit of fine asphaltum dust or powder to settle on a plate of glass in a dusting box. Coarse asphaltum can be ground finer in a mortar or a food mixer (but remember it is toxic, so the implement should be used for no other purpose). Asphaltum dust is injurious to health also when inhaled, so a respirator mask should always be used when working with it. Instead of asphaltum, an antireflex glass or a stochastic screen can also be used to make the aquatint screen.
Normally used as a waterproofing agent, asphaltum is a very thin asphalt compound.