Travertine

Travertine is a form of limestone. It is a terrestrial sedimentary rock formed by the rapid precipitation of carbonate minerals from solution in ground and surface waters, and/or geothermally heated hot-springs. Travertine often has a fibrous or concentric appearance and exists in white, tan, and cream-colored varieties. When it is formed in a limestone cave, it can form stalactites, stalagmites, and other speleothems. It is frequently used in Italy and elsewhere as a building material.