igneous
Pumice
Pumice (volcanic glass foam)
AI-generated identification · may be incorrectHardness 6 on Mohs scale, pale gray to white color, dull luster, amorphous glassy structure with abundant gas vesicles, specific gravity less than 1.0 allowing it to float.
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Physical properties
Hardness 6 on Mohs scale, pale gray to white color, dull luster, amorphous glassy structure with abundant gas vesicles, specific gravity less than 1.0 allowing it to float.
Formation & geological history
Formed during explosive volcanic eruptions when frothy, gas-rich dacitic or rhyolitic lava rapidly cools and depressurizes.
Uses & applications
Used in lightweight concrete, abrasive soaps, pumice stones for personal care, and horticulture.
Geological facts
Pumice is one of the few geological specimens that can float on water due to its high porosity.
Field identification & locations
Easily identified by its extreme lightness and vesicular, sponge-like texture; found near active and ancient volcanic regions worldwide.
