Limestone is mostly calcium, a combination of seashells and sediment that earth’s gravity crushed and formed into rock. The stone has some pitting along with visible mineral veins and fossilized shells or shell fragments. The color varies from a pale ivory to shades of red and brown, depending on the minerals present in that part of the earth’s crust. One type of limestone, travertine, has a honeycomb design but with excessive pitting from the fresh water springs where it formed.
Granite has a dense composition, making it a hard flooring stone for high traffic areas. Some stones have flecks of colored crystals that contrast with the base color of the stone. Other stones have contrasting veins that appear as stripes. Base colors include several shades of brown, red, black and white. Several base colors may appear in the same stone tile.
Marble is limestone that has crystallized. Unlike limestone, marble has a smooth texture rather than pitted. One of marble’s shortcomings as flooring material is its tendency to stain, regardless of color. Some types warp, splinter or break when they come in contact with water, including the green and black marbles. This stone works well in dry areas of the home, rather than the kitchen or dining room. Marble has veins of contrasting colors, such as white veins on brown marble.
Sandstone is comprised of quartz, which is sand and water pressed into crystals over millions of years. Like marble, sandstone is very porous yet a dense, hard stone. It needs special care when used for flooring.
Slate is a combination of shale, quartz and clay. It is a good choice for wet areas such as kitchens and patios. As the color of clay varies in different regions of the world, so does the color of slate. There are many shades of red, brown, green, orange and black.