Pumice is a gray, light volcanic glass full of air bubbles. Some pumice is light enough to float. Both Cal Poly Pomona and the University of Toledo refer to pumice as volcanic foam that has hardened. Pumice's main use is as an abrasive, and this has allowed it to find a place in health, industry and textiles.
Skin Health
Pumice stones are a common exfoliator for removing dead cells and smoothing out skin. It is a component of some abrasive soaps and can be used to help remove calluses. The University of Toledo notes that before disposable razors came on the market, pumice served as a substitute for shaving leg hairs. Pumice is also part of some wart-removal procedures, although the Healthwise Knowledgebase notes that the stone can pick up wart viruses, so any pumice used to remove dead skin in the middle of a wart treatment program should be disposed of and not used for anything else. Use it only according to the directions on the wart medicine package or per your doctor's instructions.
Dentistry
Pumice, particularly powdered pumice, is used in dentistry to polish dental porcelain and other appliances. It is also part of mixtures used by some dentists to polish tooth surfaces before applying sealant. Just as pumice can pick up wart viruses, it can also pick up other germs. Infection control procedures for institutions such as Boston University require that no pumice be reused.
Woodworking and Textiles
Pumice is one of the key ingredients in acid-washing denim. Denim is put in a drum with pumice granules and bleach. As the drum turns, the pumice wears away at the cloth as it bleaches. Pumice is also part of woodworking finishes, again for its abrasive quality. The University of Kentucky's Cooperative Extension Service says a mix of pumice and oil can give wood different levels of gloss when completing the "final rubbing" stage of wood finishing.
Industrial
Pumice's light weight has earned it a place in concrete and plaster mixes. Cal Poly Pomona says it is also used in acoustic tile and insulation, and the University of California, Berkeley, School of Journalism notes that the ceiling of Berkeley's architecture library is made of pumice concrete specifically because of its insulating qualities.
