Why do my travertine tiles have a large number of open pits and pores?
- Travertine stone naturally has open holes within it as it is a fresh water sedimentary stone where naturally water runs through it. Although sometimes people install this stone without filling those holes if they like that look; particularly on walls in dry areas. This is called unfilled travertine. Most of the time the holes in the stone are filled at the factory with special materials. This is called filled travertine. Generally speaking travertine stones with less holes, whether they are filled or not, are more desirable and more expensive. Sometimes unfilled travertine is installed first, and then they fill the holes with grout. I would not recommend unfilled travertine in showers as it would more readily allow water to get behind it and it would tend to collect debris and could develop mold in those holes.