Natural stone can produce some stunning effects when used for the decoration of bathrooms, with travertine tiles being one of the more popular options chosen.
Travertine is a naturally occurring sedimentary rock that is formed by the precipitation of calcium carbonate. It usually forms around streams, rivers, springs and swamps - one deposit outside Rome has been used for thousands of years as a source of travertine for tiles and building stone.
Small voids and cavities are created as it forms resulting in a stone that can be quite porous. When the stone is cut to form tiles these voids will be present in the tile surface. As a result of this characteristic, travertine can be supplied filled or unfilled where grout or an epoxy filler is used to plug the holes. The filler can work loose which will mean more will need to be applied over the life of the tile. Sometimes, the cutting process results in a very thin layer of the stone covering one of the cavities; pressure from foot traffic when used as a floor tile can cause the surface above the cavity to break, exposing another hole which will also need to be filled.
Filled travertine results in a smooth surface and a tile with a striking, modern appearance. Unfilled travertine provides a slightly more rustic look especially when a tumbled finish is chosen, which results in softer, less angular edges. The look of filled travertine is emulated by many ceramic tiles manufacturers but they cannot capture the look and feel of unfilled stone.
The colour of travertine can vary considerable from almost white to much darker browns and ochres. The colour variations and the striations within each tile are caused by impurities such as slay or silt being present during the formation of the stone. The slight variation in colour and the fact that no one tile will look exactly the same as another all lend to the product's natural beauty.
Travertine, as with most natural stone tiles, will need to be sealed to prevent stains from soaking into the surface and spoiling the appearance. Stone tiles also have to be cleaned carefully as harsh chemicals can adversely affect the finished surface.