Meerschaum pipe

A Meerschaum pipe is a smoking pipe made from the mineral sepiolite. Meerschaum (/ˈmɪərʃɔːm/ MEER-shawm or /ˈmɪərʃəm/ MEER-shəm, German for foam of the sea) is sometimes found floating on the Black Sea and is 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).

The first recorded use of meerschaum for making pipes was around 1723 and quickly became prized as the perfect material for providing a cool, dry, flavorful smoke. The porous nature of meerschaum draws moisture and tobacco tar into the stone. Meerschaum became a premium substitute for the clay pipes of the day and remains prized to this day though, since the mid-1800s, briar pipes have become the most common pipes for smoking.

The use of briar wood beginning in the early 1820s greatly reduced demand for clay pipes and, to a lesser degree, meerschaum pipes. The qualities of the meerschaum were combined with those of the briar wood pipes by lining a briar pipe with a meerschaum bowl. Some believe that the meerschaum-lined briar pipe gives the porosity and sweet smoking qualities of meerschaum along with the heat-absorbing qualities and durability of briar.

When smoked, meerschaum pipes gradually change color, and old meerschaum pipes will turn incremental shades of yellow, orange, red, and amber from the base on up. When prepared for use as a pipe, the natural nodules are first scraped to remove the red earthy matrix, then dried, again scraped and polished with wax. The crudely shaped masses thus prepared are turned and carved, smoothed with glass-paper, heated in wax or stearine, and finally polished with bone-ash, etc.

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Wikipedia