igneous
Pumice
Pumice (felsic volcanic rock)
AI-generated identification · may be incorrectHardness of 5.5 to 6 on the Mohs scale, typically white, grey, or cream-colored with a dull luster. It has a highly vesicular, glassy, amorphous crystal structure and is famously known for having a specific gravity less than 1, allowing it to float on water.
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Physical properties
Hardness of 5.5 to 6 on the Mohs scale, typically white, grey, or cream-colored with a dull luster. It has a highly vesicular, glassy, amorphous crystal structure and is famously known for having a specific gravity less than 1, allowing it to float on water.
Formation & geological history
Formed through the rapid cooling and depressurization of gas-rich felsic lava during explosive volcanic eruptions, preventing crystal growth and trapping gas bubbles.
Uses & applications
Extensively used in personal care for exfoliating skin, as a lightweight aggregate in concrete, in abrasive household cleaners, and for stonewashing denim.
Geological facts
Pumice is essentially volcanic glass froth. Famous geological occurrences include the eruption of Krakatoa and deposits found globally near active and extinct subduction zone volcanoes.
Field identification & locations
Easily identified by its extremely low weight, highly porous vesicular texture, and pale color. Common in volcanic regions worldwide.
