igneous
Pumice
Pumice (volcanic glass foam)
AI-generated identification · may be incorrectHardness 6 on Mohs scale, grayish to reddish brown color, dull to vitreous luster, amorphous glassy texture with abundant gas bubble vesicles, specific gravity less than 1.0.
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Physical properties
Hardness 6 on Mohs scale, grayish to reddish brown color, dull to vitreous luster, amorphous glassy texture with abundant gas bubble vesicles, specific gravity less than 1.0.
Formation & geological history
Formed during explosive volcanic eruptions when frothy, gas-rich felsic lava rapidly cools and depressurizes, trapping gas bubbles.
Uses & applications
Used widely in lightweight concrete aggregates, abrasive stones for personal care, horticulture, and industrial filtration.
Geological facts
Pumice is one of the only geological rocks that can float on water due to its extremely high porosity and trapped air bubbles.
Field identification & locations
Easily identified in the field by its very light weight, rough abrasive texture, and ability to float; commonly found near active or ancient volcanic regions.
