Wednesday, July 8, 2009

Q6143

Travertines result from hot spring water percolating up through underground limestone. When the water evaporates, it leaves behind layers of dissolved limestone and other minerals, giving it its banded appearance. The characteristic holes in travertine are the result of trapped gas bubbles; as the gas escapes, crystals form in the cavities. Yellowstone Park, for example, with its geysers and mineral springs, produces travertine. Natural travertine will have voids on the surface, and these voids are filled with cementatious or resin based filler during fabrication. In the case of cross-cut travertine, some of the holes will be near the face but will not actually window out of the face. Since these voids are not exposed during the fabrication process, they are not filled. Once in service, the thin shell of travertine separating the void from the face is not strong enough to support traffic, especially heels. The stone will "pop" out at these locations, exposing the previously undetected void. This is an expected occurrence in travertine. The holes simply need to be refilled with a similar type and color of filler material as was used in the factory. Depending upon the size and frequency of holes, this procedure may need to be repeated several times. It is analogous to a "break-in" period for the floor. Travertines are generally light-colored beiges and tans, though there are some beautiful, colored travertines that have resulted from other minerals dissolved by hot water underground.

Travertines range in hardness from 4-5 on the ten-point MOHS scale (diamonds are 10; granites are ±7), making it perfect for most areas of the home. Care does need to be taken, however when choosing material for a high-traffic area or kitchen countertops which might be subject to etching substances. Like any stone, travertine should be sealed with a penetrating sealer to prevent stains from penetrating into the stone

 

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