Carbon black is a material made from the incomplete combustion of heavy petroleum products such as coal tar, and is used in a variety of industrial and commercial applications. The two crossword solutions for the term Carbon Black are SMUT (4 letters) and SOOT (4 letters). SMUT is a type of air pollution caused by the burning of coal or other materials, and is composed of tiny particles of SOOT and ash. SOOT is a black powdery or flaky substance made up of carbon particles that is produced by the incomplete combustion of organic matter. Both SMUT and SOOT are forms of Carbon Black.