Made of clay with a manmade glaze, it has a regular thickness with the pattern or color on top instead of all the way through. If it's patterned to be a limestone look-alike, unless you look very carefully or put it right next to limestone, it looks almost identical to the real thing. Some of these floors have fossil-like imprints that are almost indistinguishable from actual limestone fossils. A second floor product made of clay is porcelain. Natural stone floors divide into two general categories according to composition.
Siliceous stone is made up of silica or quartz-like particles, is very durable and easy to clean.
Granite and slate fall into this category. The minerals in granite show as tiny flecks uniformly distributed in the stone. While granite is used more for counter tops, slate is a popular choice for floors. It comes in many colors, typically dark green, gray, black, dark red or multi-colored and because it comes out of mountains and canyons, it shows infinite choices in patterns. In the master bedroom of the Mike and Peg Groth residence in Cedarburg, Mike and his brother Mark created and installed this mosaic inlay with a limestone field.