Meerschaum /(mēr"sha̤m; 277)/

Meer·schaum

Meerschaum

n.
  1. A fine white claylike mineral, soft, and light enough when in dry masses to float in water. It is a hydrous silicate of magnesia, and is obtained chiefly in Asia Minor. It is manufacturd into tobacco pipes, cigar holders, etc. Also called sepiolite. (Min.)
  2. A tobacco pipe made of this mineral; a meerschaum pipe.