Travertine is a form of massive calcium carbonate, resulting from deposition by springs or rivers. It is beautifully coloured and banded as a result of the presence of iron compounds or other (e.g. organic) impurities. The holes characteristic of travertine were created when carbon dioxide bubbles were trapped as the stone was being formed. Travertine is available in a number of finishes ranging from polish, cross-cut, regular-cut, honed & filled, honed & unfilled, tumbled and unpolished to name a few. Travertine is offered in a wide range of colours, and covers the spectrum from pure white to deep mahogany. The various hues of Travertine can sometimes be constant throughout large pieces and at times are blended. Travertine displays distinct veins at times and is a very sturdy natural stone.