Wondering where you’ve seen this rock???.. Check your bathroom…
Pumice is a light-colored, extremely porous igneous rock that forms when highly pressurized, super-heated molten rock, with its incorporated water and gases, violently erupts to the surface during volcanic explosions. The rock undergoes rapid cooling and rapid depressurization and the vapour dissolved in it is suddenly released and the whole mass swells up into a froth that is immediately consolidated.
Small crystals of various minerals occur in many pumices especially feldspar, augite, hornblende, and zircon. Pumice in old volcanic rocks has cavities filled usually with deposits of secondary minerals introduced by percolating water. Pumice is highly porous and easily floats on water, although it sinks after absorbing sufficient amounts of water. Its pale, light color, ranging from white to grey to green-brown, indicates that it is high in silica content, and low in iron and magnesium content.
It’s an ideal abrasive material due to its friable, separable nature; usually used in cosmetics for exfoliate purposes (eg in manicure and pedicure procedures), in polishes, pencil erasers, and for softening and aging textiles like denims. Also use as a lightweight concrete material and in blast mitigation (the porous chambers hold potential to absorb blast energy). Pumice is also used in large-scale water filtration systems, and in the paint, rubber, and plastics industries as a functional filler.
#pumice #rocks #knowrocks #geology #mining #mininghubafrica