igneous
Pumice
Pumice (volcanic glass foam)
AI-generated identification · may be incorrectHardness 6 on Mohs scale, gray to white color, dull to vitreous luster, amorphous volcanic glass structure with abundant gas vesicles, specific gravity less than 1.
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Physical properties
Hardness 6 on Mohs scale, gray to white color, dull to vitreous luster, amorphous volcanic glass structure with abundant gas vesicles, specific gravity less than 1.
Formation & geological history
Formed during explosive volcanic eruptions when frothy, gas-rich felsic lava rapidly cools and depressurizes, trapping gas bubbles.
Uses & applications
Used in lightweight concrete, landscaping, abrasive soaps, pumice stones for personal care, and horticulture as a soil amendment.
Geological facts
Pumice is one of the few natural rocks that can float on water due to its high porosity and trapped gas bubbles.
Field identification & locations
Easily identified by its extremely light weight, pale color, and vesicular texture filled with tiny cavities; commonly found near active or ancient volcanic regions worldwide.
