The happening between previous volcanic rocks, the cavities are generally stuffed with deposits of secondary minerals released by percolating drinking water. The glass by itself varieties threads, fibres, and slim partitions involving the vesicles. Rhyolite and trachyte pumices are white, andesite pumices generally yellow or brown, and pumiceous basalts (such https://edenproductsltd.co.uk/2025/04/17/the-history-of-pumice-stone-from-ancient-civilisations-to-modern-day-uses/