The term can be employed synonymously with "volcanic ash." It can be mined from volcanic ash deposits, or it can be produced by crushing rock pumice. "From June 7 to 12, the main magma reached the area of Mount Pinatubo. Because it had shed the vast majority of gas contained https://edenproductsltd.co.uk/2025/04/17/the-history-of-pumice-stone-from-ancient-civilisations-to-modern-day-uses/