Travertine

Travertine is a white massive concretionary form of calcium carbonate, CaCO3 which is a resultant of deposition by springs (especially hot springs) or rivers. Travertine is usually hard and semicrystalline. It is often found in a beautifully coloured and banded as a result of the iron compounds presence or some other impurities. Generally travertine is less coarse-grained and takes a higher polish than stalactite or stalagmite whose chemical composition and origin are similar.