igneous
Pumice
Pumice (volcanic glass foam)
AI-generated identification · may be incorrectHardness 6 on Mohs scale, color ranges from white to grey or yellowish, luster is dull to earthy, amorphous glass structure with extremely high porosity allowing it to float on water.
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Physical properties
Hardness 6 on Mohs scale, color ranges from white to grey or yellowish, luster is dull to earthy, amorphous glass structure with extremely high porosity allowing it to float on water.
Formation & geological history
Formed through the explosive eruption of silica-rich magma where rapid pressure drop causes dissolved gases to exsolve and foam the cooling lava.
Uses & applications
Widely used in lightweight concrete, abrasive products, personal care pumice stones, and horticulture for soil aeration.
Geological facts
Pumice is one of the few geological materials that can float on water due to its trapped gas bubbles. It forms an essential component of Roman concrete, contributing to its extreme durability.
Field identification & locations
Easily identified by its exceptionally low density, frothy texture, and pale coloration. Found globally near active or historical volcanic regions.
