Peruvian Travertine has become the leader and "go to" product for swimming pool application. Inca Stone's Peruvian Travertine is one of the only natural stones in the industry that can be used in waterline and submersible application in swimming pools. Being that our Peruvian Travertine has tested with 99.9% Calcium Carbonate, the most reliable and stable Calcium you can have in a natural stone, Muriatic acids, chlorine, and saline pools do not affect our stone; unlike other natural stones, pre-cast, and concrete products.