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.