What's That Rock?Pumice
A frothy volcanic rock filled with gas bubbles. It is light enough to float on water.
How to identify Pumice
- Full of small holes
- So light it floats
- Rough and scratchy
Often confused with
- Scoriadarker, heavier
- Lightweight man-made materials
Is Pumice valuable?
Inexpensive.
What changes the price
- Common rock: very low value
- Sold as a bath, craft and cleaning stone for a few dollars
- Large or unusual pieces are only décor
Uses
- Skin exfoliation, polishing, lightweight concrete
Care
Brittle; crumbles with rough handling.
Identifying a stone from a description or a photo is an estimate. Many stones look alike. Ask an expert or a gem lab before you buy, sell or rely on an identification.
Updated October 2026