Meerschaum is a soft white, gray, or cream-colored mineral named magnesium silicate. The name comes from the German word for seafoam, because it was sometimes found floating in the Black Sea and people thought it was pertrified seafoam. Meerschaum is soft when first extracted, but it quickly hardens when heated. Pipes and other pieces of carved meerschaum listed here date from the nineteenth century to the present.