Asbestos (a misapplication of Latin: asbestos "quicklime" from Greek ἄóâåóôïò: a, "not" and sbestos, "extinguishable") describes any of a group of fibrous metamorphic minerals of the hydrous magnesium silicate variety. The name is derived for its historical use in lamp wicks; the
resistance of asbestos to fire has long been exploited for a variety of purposes. Asbestos was used in fabrics such as
Egyptian burial cloths and Charlemagne's tablecloth which according to legend, he threw in a fire to clean. Asbestos occurs naturally in many forms (see below); it is mined from metamorphic rocks.
When asbestos is used for its
resistance to fire or heat, the fibers are
often mixed with cement or woven into fabric or mats. Asbestos is used in brake shoes and gaskets for its heat resistance, and in the past was used on electric oven and hotplate wiring for its
electrical insulation at elevated temperature, and in buildings for its flame-retardant and insulating properties, tensile strength, flexibility, and resistance to chemicals. The inhalation of some kinds of asbestos fibers, however, causes various serious illnesses, including cancer. Thus, most uses of asbestos are banned in many countries. Fiberglass or Synthetic Mineral Fibre has been found to be a suitable substitute for thermal insulation, and woven ceramic fiber performs as well as or better than asbestos as an insulator of high-temperature
electrical conductors
