Travertine is a limestone composed by chemical deposit, formed by calcium carbonate precipitation or by rapid temperature and pressure variations or by the action of certain organisms like seaweeds or bacteria. It's characterized by a porous and cavernous structure, due largely to the spaces left by the vegetables of the basins powered by these waters that, absorbed by the calcareous encrustation, then disappeared for decomposition. It has got a typical white color, slightly yellow or very light red and it comes up with a more or less evident stratification.
