A light, porous rock formed by consolidation of volcanic ash.
‘Among the 30 different types of stone recognized are varieties of diorite, granite, bedded tuff, sandstones, limestones, and tufa.’
‘Lenses incorporate varicoloured tuffaceous cherts intercalated with tuffaccous mudstone and tuff.’
‘The lower series consists of alternating basalt lava, tuff breccia, tufite, and siliceous rock, whereas the upper one is dominated by diabase.’
‘Increasing proximity to a subduction zone during plate convergence is indicated by the appearance of felsic tuff.’
‘It also follows that there are differences in age between grains, which is consistent with the impression of resorption given by the grain morphology: possibly all grains predate the final tuff volcanism.’
Origin
Mid 16th century via French from Italian tufo, from late Latin tofus, Latin tophus (see tophus).
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