The word can be employed synonymously with "volcanic ash." It is mined from volcanic ash deposits, or it can be made by crushing rock pumice. Geologists detect prospective pumice deposits by researching volcanic activity and examining surface outcrops of volcanic rocks. Aerial surveys and floor-based mostly sampling in many cases https://edenproductsltd.co.uk/2025/04/17/the-history-of-pumice-stone-from-ancient-civilisations-to-modern-day-uses/