MEERSCHAUM

n. sepiolite, hydrous magnesium silicate (Geology); tobacco pipe made from meerschaum

is a soft white mineral sometimes found floating on the Black Sea, and rather suggestive of sea-foam (German: Meerschaum), whence also the French name for the same substance, écume de mer. It was termed by E. F. Glocker sepiolite, in allusion to its remote resemblance to the bone of the sepia or cuttlefish. Meerschaum is opaque and of white, grey or cream color, breaking with a conchoidal or fine earthy fracture, and occasionally fibrous in texture. Because it can be readily scratched with the nail, its hardness is placed at about 2. The specific gravity varies from 0.988 to 1.279, but the porosity of the mineral may lead to error. Meerschaum is a hydrous magnesium silicate with the formula H4Mg2Si3O10.
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Noun
1. a white clayey mineral
(synonym) sepiolite
(hypernym) mineral
2. a pipe having a bowl made of meerschaum
(hypernym) pipe, tobacco pipe
(substance-meronym) sepiolite

n. meerschaum, sepiolite, hydrous magnesium silicate (Geology); tobacco pipe made from meerschaum

(n.)
A tobacco pipe made of this mineral.
  

(n.)
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.