Marble is a rock widely used in buildings, monuments, and sculptures. It consists chiefly of calcite or dolomite, or a combination of these carbonate minerals. Marble is a type of metamorphic rock formed from limestone. Marble is found in many countries, including Belgium, France, Great Britain, Greece, India, Italy, and Spain.
Marble is formed from limestone by heat and pressure in the earth’s crust. These forces cause the limestone to change in texture and makeup. This process is called recrystallization. Fossilized materials in the limestone, along with its original carbonate minerals, recrystallise and form large, coarse grains of calcite. Impurities present in the limestone during recrystallization affect the mineral composition of the marble that forms. The minerals that result from impurities give marble wide variety of colors. The purest calcite marble is white. Marble containing hematite has a reddish color. Marble that has limonite is yellow, and marble with serpentine is green.
Marble does not split easily into sheets of equal size and must be mined carefully. The rock may shatter if explosives are used. Blocks of marble are mined with channeling machines, which cut grooves and holes in the rock,
Uses. Marble has long been highly valued for its beauty, strength, and resistance to fire and erosion. The ancient Greeks used marble in many buildings and statues. The Italian artist Michelangelo used marble from Carrara, Italy, in a number of sculptures.
Extremely pure calcite marble is used for most statues. Large blocks of colored marble are, used for columns, floors, and other parts of buildings. Smaller pieces of such marble are crushed or finely ground and used as abrasives in soaps and other products. Crushed or ground marble is also used in paving roads and in manufacturing roofing materials and soil treatment products.
Marble is limestone that has crystallized naturally over a period of time. Marble is classified into four groups, Groups A, B, C, and D. These are broad classifications and relate only to soundness and working qualities. However, for the purpose of this maintenance guide marble has been classified as exterior or interior maintenance of marble. The test used for water absorption is ASTM C97. Marble is cut into blocks, slabs or tile in various thickness and sizes. Marble flooring is very sensitive to acids and alkalis and can be stained if spills are not wiped up immediately. If marble flooring is installed in an area where staining liquids are liable to cause problems, then the flooring should be sealed and finish applied.
Marbles are basically metamorphosed limestones. Once limestone is subjected to heat and pressure, the calcium carbonate re crystallizes into marble.
Marbles have similar characteristics to limestones and are typically used on the same applications, though, marbles are almost always more aesthetically valuable and available in much wider range of colors.
There are several types of marbles, including calcites (from calciferous limestones), dolomites (from dolomitic limestone), serpentines (typically green marbles) and travertines (sedimentary limestone). Each of these is similar in their composition, that being predominantly calcium carbonate, and their capability to take a polish. The stone that is quarried west of Belen in central New Mexico is a travertine marble.
Many years ago, there was a cataclysmic shift in the earth’s crust and the Rio Grande Valley appeared. The Sandia mountains were pushed up on the east side bringing granite to the surface and leaving limestone on the top or backside of the mountain. This limestone was once the floor of a vast ocean that covered the entire southwest U.S. If you drive along south 14 you can see the layers of limestone along the roadside. This same limestone is used to make cement at the plant in Tijeras, New Mexico. When the valley was formed, there were openings made in the earth’s crust which allowed volcanoes to form and many hot springs to appear. These hot springs were present west of Belen, and as they came to the surface, the water passed through the limestone beds.
The calcium carbonate in the limestone went into suspension in the water and once it got to the surface the water evaporated and it became travertine.
One characteristic of all Travertines is the presence of small voids that were caused by air bubbles in the hot water. At times when the springs went cold, onyx was formed. It is not uncommon to find bands of onyx among travertine beds.
Marbles are suitable for both interior and exterior applications but it should be noted that with today’s environment containing so many pollutants, if a polish finish is specified on marble, it will not last.