What is Travertine?
[[Image:Yellowstone p1100309 rotated.jpg|thumb|200px|Travertine terraces at Mammoth Hot Springs, [[Yellowstone National Park]]]] [[Image:Kalktuff-Mosscrusts.jpg|thumb|200px|Calcium-carbonate-encrusted, yet growing moss, early stage of porous travertine formation.]] '''Travertine''' is a [[Land|terrestrial]] [[sedimentary rock]]. It is a natural chemical [[precipitation|precipitate]] of [[carbonate]] [[mineral]]s; [[aragonite]] or [[calcite]]. This happens from solution in ground and surface waters, and/or [[hot spring|geothermally heated hot-springs]].<ref>''Dictionary of geological terms'', 1962. A Dolphin Reference Book</ref><ref>''A glossary of karst terminology'', 1970. Geol. Surv. Water-Supply Paper 1899-K, U. S. Gov. Print. Off., Washington.</ref> Similar (but extremely [[wikt:porous|porous]]) deposits formed from ambient-temperature water are known as [[tufa]]. The [[Colosseum]] built by the [[Roman Empire|Romans]], was made of travertine. == References == {{Reflist}} [[Image:Kalktuff-Block Schloss-Tuebingen 2.jpg|thumb|left|200px|Travertine in a 400 year old wall of the castle Hohen [[Tübingen]]. The material is extremely hard and weatherproof. The cavities and impurities - remnents of small debris, scrub and biotic materials - make the rock porous and lightweight.]] {{science-stub}} [[Category:Carbonate rocks]]