Pumice is a highly vesicular pyroclastic igneous rock of intermediate to siliceous magmas including rhyolite, trachyte and phonolite.
Pumice is usually light in colour ranging from white, yellowish, gray, gray brown, and a dull red.
Pumice has an average porosity of 90%.
Pumice is formed as pyroclastic material is ejected into the air as a froth containing masses of gas bubbles or vessicles, the lava solidifies quickly and the vessicles are contained in the rock.
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