Sepiolite, also known in English name meerschaum MEER-shawm -shəm ( listen ); meaning "sea foam , often used to make tobacco pipes (known as meerschaum pipes, a typical chemical formula for which is Mg4Si6O15(OH)2·6H2O, it can be present in fibrous, fine-particulate, and solid forms.
Originally named meerschaum by Abraham Gottlob Werner in 1788, it was named sepiolite by Ernst Friedrich Glocker in 1847 for an occurrence in Bettolino, Torino Province. The name comes from Greek " (the porous internal shell of the cuttlefish), + lithos (λίθος), meaning stone, after a perceived resemblance of this mineral to cuttlebone. Because of its low specific gravity and its high porosity, it may float upon water, hence its German name. It is sometimes found floating on the Black Sea and rather suggestive of sea-foam, hence the German origin of the name as well as the French name for the same substance, écume de mer.