igneous
Pumice
Pumice
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale, pale gray to yellowish-brown color, vitreous to dull luster, and highly vesicular amorphous volcanic glass structure with a very low specific gravity that allows it to float on water.
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Physical properties
Hardness of 6 on the Mohs scale, pale gray to yellowish-brown color, vitreous to dull luster, and highly vesicular amorphous volcanic glass structure with a very low specific gravity that allows it to float on water.
Formation & geological history
Formed through the explosive eruption of silica-rich felsic magma, where rapid pressure release causes dissolved gases to froth and freeze the lava into a porous foam.
Uses & applications
Widely used in lightweight concrete, abrasive cleaning products, personal care exfoliating stones, and horticultural soil amendments.
Geological facts
Pumice is one of the only volcanic rocks capable of floating on water due to its trapped gas bubbles. It is frequently associated with catastrophic pyroclastic flows.
Field identification & locations
Easily identified by its extremely low density, floating capability, and frothy, sponge-like vesicular texture. Commonly found near active and historical volcanic arcs worldwide.
