In the Nineteenth Century, artisans in Eastern Europe made amazing smoking pipes out of meerschaum, a soft mineral. Roy Ricketts has assembled a collection of outstanding examples of this crafting tradition. Ben Marks of Collectors' Weekly explains why craftsmen used meerschaum:
Meerschaum is a relatively new material to pipe making, appearing no earlier than the 18th century. Found primarily in and around the city of Eskişehir in western Turkey, meerschaum is a porous mineral that’s soft enough to be carved but hard enough to be polished, revealing the carver’s artistry. Unlike hardwood briar pipes, which are also finely carved, meerschaum does not burn, which means the bowl is cool to the touch when it’s being smoked and the pipe material imparts no flavor to the tobacco. And because meerschaum is porous, meerschaum pipes change color over time as they are smoked. Thus, the stone, which is carved white, turns butterscotch brown when made into a pipe, filled with tobacco, and smoked, a process that’s frequently hurried along by rubbing a finished pipe with beeswax and, occasionally, ox blood.
At the link, you can see more photos of pipes in Mr. Ricketts's collection.