Meerschaum Pipe.

Meerschaum is a German word meaning sea foam. It is opaque and of white, grey or cream color, breaking with a conchoidal or fine earthy fracture, and occasionally though rarely, fibrous in texture.
Unlike Briar which must be dried after each smoke, Meerschaum can be smoked many times a day because of its absorbing qualities .www.apothecaryedinburgh.co.uk