What is Pumice?
[[Image:Teidepumice.jpg|thumb|Specimen of highly porous pumice from [[Teide]] volcano on [[Tenerife]], [[Canary Islands]]. [[Density]] of specimen approx 0.25 g/cm³. Scale is in [[Metre#SI_multiples|centimeters]].]] [[File:Pumice stone detail444.jpg|thumb|Illustrates the porous nature in detail]] '''Pumice''' is a term for a lightweight [[Volcano|volcanic]] [[Rock (geology)|rock]]. It is a solidified [[froth]]y [[lava]], created when highly-heated, pressured molten rock is shot out from a volcano. Its light weight is due to air spaces, which are caused by fast cooling and loss of [[pressure]]. The loss of pressure makes [[wikt:bubble|bubbles]] by lowering the [[boiling point]] of the lava (like the bubble-creation when a carbonated drink is opened). The cooling then freezes the bubbles in [[The Matrix|the matrix]]. == Uses == Most famously, pumice stone has been used as a skin-scraper. It is used in [[pedicure]] to remove excess skin from the bottom of the foot, and on [[callus]]es (tough areas of skin). It has also been used to make lightweight blocks for building, and as a powdered [[ingredient]] in polishing. {{Rock type}} {{-}} {{sci-stub}} [[Category:Igneous rocks]]