Travertine

Travertine terraces at Mammoth Hot Springs, Yellowstone National Park

Calcium-carbonate-encrusted, yet growing moss, early stage of porous travertine formation.

Travertine is a terrestrial sedimentary rock. It is a natural chemical precipitate of carbonate minerals; aragonite or calcite. This happens from solution in ground and surface waters, and/or geothermally heated hot-springs.^[1]^[2] Similar (but extremely porous) deposits formed from ambient-temperature water are known as tufa.

The Colosseum built by the Romans, was made of travertine.

Travertine Media

Travertine terraces at Mammoth Hot Springs, Yellowstone National Park, in 2016
Badab-e Surt's stepped travertine terrace formations. This travertine owes its red colour terraces to iron carbonate.
Mausoleum submerged in a travertine pool at Hierapolis hot springs, Turkey
Soda Dam, Jemez Mountains, New Mexico
Sacré-Cœur, Paris, (1875–1914)
Burghausen Castle, Europe's longest castle, is 1,000 years old and built mainly with travertine.
Travertine vessels found in El Tapesco del Diablo Cave in Ocozocoautla, Chiapas, Mexico (600–900 AD)

References

↑ Dictionary of geological terms, 1962. A Dolphin Reference Book
↑ A glossary of karst terminology, 1970. Geol. Surv. Water-Supply Paper 1899-K, U. S. Gov. Print. Off., Washington.

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.

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[1] Dictionary of geological terms, 1962. A Dolphin Reference Book

[2] A glossary of karst terminology, 1970. Geol. Surv. Water-Supply Paper 1899-K, U. S. Gov. Print. Off., Washington.

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