Marble & Other Stone
Marble
Marble consists mainly of crystallized calcium carbonate but other iron and clay minerals may be present which add colour, either as a base or in the veins. It will usually accept polishing to a high gloss. Marble is quarried throughout the world although today, it is usually sourced in Italy, Spain and Portugal.
Although a pattern is often consistent throughout a block, marble is a natural substance with inevitable variations of colour and appearance, which makes precise colour matching both impossible and undesirable. This is, of course, what gives marble its charm, individuality and unique quality.
Limestone
The muted tones of limestone are perfect for today’s more casual and comfortable lifestyles. Generally these soft beiges and tans, either polished or honed, are appropriate for bathrooms, fireplaces, counters and less‐traveled flooring where a more informal decor is desired.
Limestone has been used as exterior building cladding since time immemorial. Though most of it is gone, looted to build other structures, the Great Pyramids in Egypt were originally clad in smooth, perhaps even polished, limestone, as are many of the great cathedrals of Europe, such as Notre Dame in Paris. Sadly, many of these have fallen victim to a more modern menace, the acids found in polluted air, which have actually dissolved the surfaces and deteriorated the stone.
Though limestone is primarily calcareous – composed of the mineral compound calcium carbonate – other minerals present in the sediments produce various colors. Heat and pressure have a dramatic effect on the density and appearance of limestones. Beaumaniére and Gascogne, for example, are less hard than Rojo Alicante, New Pink, and Crema Marfil. Those latter three stones will take a high polish, and are usually classified commercially as marble.
Slate
Beautiful and soft to the touch, slate is much more than just a building material. Slate evokes tradition, authenticity and distinction. It continues our rich heritage and demonstrates our renewed interest for living in harmony with nature. Slate is a fine‐grained rock formed by the composition of mud and stone sediment. It is a form of metamorphic rock that consists of silica alumina and iron oxide. It can be easily split into layers that can provide a beautiful rugged look. Slate is an excellent choice for entrances, sunrooms and bathrooms, but can also be used in the kitchen for a rustic look.
When it is correctly cut, it has good abrasion resistance and long lasting durability. Being a natural material, slate is found beneath the earth’s surface in many countries throughout the world. Most of it commercially comes from the quarries in India, China, Africa, Brazil, USA and Italy.
Travertine
Most travertine used as a gem rock or decorative stone is white, tan or cream colored, fairly dense (though porous) rock that consists largely of calcite; some of it, however, consists in part or wholly of aragonite.
Travertines result from hot spring water percolating up through underground limestone. When the water evaporates, it leaves behind layers of dissolved limestone and other minerals, giving it its banded appearance. The characteristic holes in travertine are the result of trapped gas bubbles; as the gas escapes, crystals form in the cavities. Yellowstone Park, for example, with its geysers and mineral springs, produces travertine. Travertines are generally light‐colored beiges and tans, though there are some beautiful, colored travertines that have resulted from other minerals dissolved by hot water underground.