Travertine:

Travertine is a type of limestone formed by hot springs. The movement of water gives travertine its familiar stripes and the gasses within cause bubbles and holes within the stone, which we call pits. Coloration stays very neutral, beige and gray being the predominate tones. As with Limestone, it’s porous and not suitable for high traffic areas and is subject to staining if not sealed often.

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