The phrase may be used synonymously with "volcanic ash." It is mined from volcanic ash deposits, or it may be produced by crushing rock pumice. 【Normal STONE】- Lava pumice stone can be a purely natural and porous stone with delicate abrasive characteristics, that makes it a porous material. Make use https://edenproductsltd.co.uk/2025/04/17/the-history-of-pumice-stone-from-ancient-civilisations-to-modern-day-uses/