The term can be used synonymously with "volcanic ash." It's mined from volcanic ash deposits, or it could be made by crushing rock pumice. There's two different types of exfoliation: chemical, in which you use skin care goods or chemical compounds to gently clear away useless pores and skin cells, https://edenproductsltd.co.uk/2025/04/17/the-history-of-pumice-stone-from-ancient-civilisations-to-modern-day-uses/