concept

Permineralization

The commonest fossilization route, and the one that makes petrified wood. Groundwater carrying dissolved minerals seeps into the empty spaces left inside wood or bone - vessels, Haversian canals, marrow cavities - and the minerals precipitate out, filling them. The essential point: it does *not* destroy the original framework but fills the voids inside it, so cellular detail can survive intact. In wood, dissolved silica crystallizes first to opal and eventually to microcrystalline quartz.