Floor tiles are commonly made of ceramic or stone, although recent technological advances have resulted in glass tiles for floors as well. Ceramic tile may be painted and glazed. Small mosaic tiles may be laid in various patterns--both glass and porcelain tile can be utilized for these projects. Floor tiles are typically set into mortar consisting of sand, cement, and often a latex additive for extra adhesion. The spaces between the tiles are nowadays filled with sanded or un-sanded floor grout, but mortar traditionally served this purpose in tile flooring. The versatility of tiles in terms of installation has even led to the increased popularity of products like carpet tile.
Natural stone tiles can be beautiful but, as a natural product, they are less uniform in color and pattern than manufactured products such as laminate tile. They also require more planning for use and installation. Mass-produced stone tiles are uniform in width and length. Granite or marble tiles are sawn on both sides and then polished or finished on the wear surface so that they have a uniform thickness. Other natural stone tiles such as slate are typically split on the wear surface so that the thickness of the tile varies slightly from one spot on the tile to another and from one tile to another. Variations in tile thickness can be handled by adjusting the amount of mortar used under the tile, by using wide grout lines that "ramp" between different thicknesses, or by using a cold chisel to knock off high spots.
Some stone tiles such as polished granite and marble are very slippery when wet. Stone tiles with a riv?en (split) surface such as slate or with a sawn and then sandblasted or honed surface will be more slip resistant. Ceramic tile that is going to be used in wet areas can be made more slip resistant either by using very small tiles so that the grout lines acts as grooves or by imprinting a contour pattern onto the face of the tile.
The hardness of natural stone tiles varies such that some of the softer stone (e.g. limestone) tiles are not suitable for very heavy traffic floor areas. On the other hand, ceramic tiles typically have a glazed upper surface and when that become scratched or pitted the floor looks worn, whereas the same amount of wear on natural stone tiles won't show, or will be less noticeable. Natural stone tiles can be stained by spilled liquids; they must be sealed and periodically resealed with a sealant in contrast to ceramic tiles which only need their grout lines sealed. However, because of the complex, non repeating patterns in natural stone, small amounts of dirt on many natural stone floor tiles do not show. Stone tiles will have variation in color and pattern from one batch of tiles to another of the same description and variation within the same batch. Stone floor tiles tend to be heavier than ceramic tiles and somewhat more prone to breakage during shipment.
