Meerschaum
Meerschaum (mēr"sham; 277) , noun
[German, lit., sea foam; meer sea + schaum foam; but it perh. is a corruption of the Tartaric name myrsen. Compare Mere a lake, and Scum.]
1.
(Mineralogy) 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 manufactured into tobacco pipes, cigar holders, etc. Also called sepiolite.
2.
A tobacco pipe made of this mineral; a meerschaum pipe.