Marble as a natural stone- properties and types

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Marble as a natural stone- properties and types
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What is Marble?

• Marble is a metamorphic rock that forms
  when limestone is subjected to the heat and
  pressure of metamorphism. It is composed
  primarily of the mineral calcite (CaCO3) and
  usually contains other minerals, such as clay
  minerals, micas, quartz, pyrite, iron oxides,
  and graphite. Under the conditions of
  metamorphism, the calcite in the limestone
  recrystallizes to form a rock that is a mass of
  interlocking calcite crystals. A related rock,
  dolomitic marble, is produced when dolo stone is
  subjected to heat and pressure.

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How Does Marble Form?

• Most marble forms at convergent plate boundaries
  where large areas of Earth's crust are exposed to
  regional metamorphism. Some marble also forms by
  contact metamorphism when a hot magma body heats
  adjacent limestone or dolo stone.
• Before metamorphism, the calcite in the limestone
  is often in the form of lithified fossil material
  and biological debris. During metamorphism, this
  calcite recrystallizes and the texture of the
  rock changes. In the early stages of the
  limestone-to-marble transformation, the calcite
  crystals in the rock are very small. In a
  freshly-broken hand specimen, they might only be
  recognized as a sugary sparkle of light
  reflecting from their tiny cleavage faces when
  the rock is played in the light.

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• As metamorphism progresses, the crystals grow
  larger and become easily recognizable as
  interlocking crystals of calcite.
  Recrystallization obscures the original fossils
  and sedimentary structures of the limestone. It
  also occurs without forming foliation, which
  normally is found in rocks that are altered by
  the directed pressure of a convergent plate
  boundary.
• Recrystallization is what marks the separation
  between limestone and marble. Marble that has
  been exposed to low levels of metamorphism will
  have very small calcite crystals. The crystals
  become larger as the level of metamorphism
  progresses. Clay minerals within the marble will
  alter to micas and more complex silicate
  structures as the level of metamorphism increases

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Physical Properties and Uses of Marble

• Marble occurs in large deposits that can be
  hundreds of feet thick and geographically
  extensive. This allows it to be economically
  mined on a large scale, with some mines and
  quarries producing millions of tons per year.
• Most marble is made into either crushed stone or
  dimension stone. Crushed stone is used as an
  aggregate in highways, railroad beds, building
  foundations, and other types of construction.
  Dimension stone is produced by sawing marble into
  pieces of specific dimensions. These are used in
  monuments, buildings, sculptures, paving and
  other projects. We have an article about "the
  uses of marble" that includes photos and
  descriptions of marble in many types of uses.

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• Color   Marble is usually a light-colored rock.
  When it is formed from a limestone with very few
  impurities, it will be white in color. Marble
  that contains impurities such as clay minerals,
  iron oxides, or bituminous material can be
  bluish, gray, pink, yellow, or black in color.
• Marble of extremely high purity with a bright
  white color is very useful. It is often mined,
  crushed to a powder, and then processed to remove
  as many impurities as possible. The resulting
  product is called "whiting." This powder is used
  as a coloring agent and filler in paint,
  whitewash, putty, plastic, grout, cosmetics,
  paper, and other manufactured products.

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• Acid Reaction   Being composed of calcium
  carbonate, marble will react in contact with many
  acids, neutralizing the acid. It is one of the
  most effective acid neutralization materials.
  Marble is often crushed and used for acid
  neutralization in streams, lakes, and soils.
• It is used for acid neutralization in the
  chemical industry as well. Pharmaceutical antacid
  medicines such as "Tums" contain calcium
  carbonate, which is sometimes made from powdered
  marble. These medicines are helpful to people who
  suffer from acid reflux or acid indigestion.
  Powdered marble is used as an inert filler in
  other pills.

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• Hardness   Being composed of calcite, marble has
  a hardness of three on the Mohs hardness scale.
  As a result, marble is easy to carve, and that
  makes it useful for producing sculptures and
  ornamental objects. The translucence of marble
  makes it especially attractive for many types of
  sculptures.
• The low hardness and solubility of marble allows
  it to be used as a calcium additive in animal
  feeds. Calcium additives are especially important
  for dairy cows and egg-producing chickens. It is
  also used as a low-hardness abrasive for
  scrubbing bathroom and kitchen fixtures.

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• Ability to Accept a Polish   After being sanded
  with progressively finer abrasives, marble can be
  polished to a high luster. This allows attractive
  pieces of marble to be cut, polished, and used as
  floor tiles, architectural panels, facing stone,
  window sills, stair treads, columns, and many
  other pieces of decorative stone.

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Marble companies in uae

• Natural Stone TR. L.L.C SharjahP.O.Box.
  69128United Arab Emirates971 6 5741607 971
  564081731 contactus_at_naturalstoneuae.com