igneous
Pumice
Pumice (felsic volcanic rock)
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, typically light gray to tan in color, dull luster, highly vesicular amorphous glass structure with no cleavage, and an extremely low specific gravity that allows it to float on water.
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Physical properties
Hardness of 6 on the Mohs scale, typically light gray to tan in color, dull luster, highly vesicular amorphous glass structure with no cleavage, and an extremely low specific gravity that allows it to float on water.
Formation & geological history
Formed through the rapid cooling and depressurization of gas-rich felsic lava during explosive volcanic eruptions.
Uses & applications
Widely used in lightweight concrete aggregates, abrasive personal care products like pumice stones, and horticultural soil amendments.
Geological facts
Pumice is one of the only rocks that can float on water due to its trapped gas bubbles forming a frothy glass matrix.
Field identification & locations
Easily identified by its extremely low density, light weight, and distinct vesicular texture riddled with small holes. Found globally near active or historical convergent plate boundaries and volcanic arcs.
