Thae act or process of combining or impregnating with silicon or silica; the state of being so combined or impregnated; as, the silicification of wood.
when water, containing dissolved silica salts, is repeatedly evaporated from a surface, the silica residue builds up in a 'concreting' effect and the layer becomes progressively harder. It may, in time, be turned into quartz..
Alteration process involving the introduction of, or replacement by, silica, generally resulting in the formation of fine-grained quartz, chalcedony, or opal, which may fill pores and replace existing minerals.