The fabric cools so speedily that atoms in the melt are not able to organize on their own into a crystalline structure. As a result, pumice is surely an amorphous volcanic glass often called a "mineraloid." "From June 7 to 12, the primary magma achieved the surface of Mount Pinatubo. https://edenproductsltd.co.uk/2025/04/17/the-history-of-pumice-stone-from-ancient-civilisations-to-modern-day-uses/