All Stone Is Not Alike
There are several different types of building stone. The most common are granite, marble, limestone, travertine and sandstone. Each stone has unique physical characteristics which affect its applicability to various building designs. This section describes the characteristics and physical properties of these major building stones.

Granite >> See samples

Granite is an igneous rock created deep within the earth from magma, cooled slowly under great pressure. It is the hardest building stone with a very dense grain, making it virtually impervious to stain. It takes a highly polished finish which will endure even in inclement environments. It also can be finished in a variety of other ways. There is a broad spectrum of granite colors ranging from nearly pure white to nearly pure black. Granite may also be infused with other minerals providing patterned "movement" as well as color.

Marble >> See samples

Marble is a metamorphic rock, composed of metamorphosized limestone. In its purest form, marble is crystalline white calcite. Most marbles, however, are infused with impurities such as dolomite, silica or clay, providing variations in color and significant movement. The base colors of marble range from white to black with a broad range of hues. Marble is significantly softer than granite and, therefore, subject to greater wear and weathering. Corners are more susceptible to chipping; fissures in the surface may trap water, which subsequently freezes and cracks the stone. Marble will stain and, therefore, is not suitable where it will be exposed to harsh air pollutants and/or chemicals or dyes, including those common in many foods.

Travertine >> See samples

Travertine displays characteristics similar to limestone. It is layered calcium carbonate formed by deposits from spring water, particularly hot springs. Metamorphosized travertine is marble-like and takes a polish.

Slate >> See samples

Slate, which is a metamorphic material, can be characterized by a sheet-like structure with parallel cleavage. It's composed of clay, quartz and mica and comes in a multitude of colors. Natural slate is very much in demand today.