the.com/pumice stone
Lava that got so excited escaping the volcano it turned into foam, then rock.
means A light, rough volcanic rock so full of trapped air bubbles it can float on water, used for scrubbing away dead skin or buffing rough surfaces smooth.
from The word traces back to Latin 'pumex,' meaning foam or froth-rock, itself likely related to 'spuma,' the Latin word for foam — the same root that gives English 'spume.' The name fits: pumice forms when gas-charged, frothy lava cools so fast the bubbles get frozen in place forever, leaving a stone that's riddled with tiny air pockets, light enough to float.
- float test
- Floats on water thanks to trapped gas bubbles.
- origin
- Forms when erupting lava cools almost instantly in air.
- actual use
- Exfoliates feet by sanding off dead skin, literally.
- space cousin
- Similar foamy rock has been found on Mars.