Travertine is a type of natural stone formed through massive calcium carbonate, CaCO3, and resulting from deposition by springs or land rivers. Travertine is very porous but consists of very fine grains,

Travertine is a type of natural stone formed through massive calcium carbonate, CaCO3, and resulting from deposition by springs or land rivers. Travertine is very porous but consists of very fine grains, often carries beautiful banded colors as the result of presence of iron compound or other impurities such as organics. Travertine stone, sometime being called "travertine marble", "travertine limestone", is also known as calc-sinter and calcareous tufa; Another nickname for travertine is "Egyptian Oriental alabaster".