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 colours. The purest calcite marble is white. Marble containing
hematite has a reddish colour. 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 Michaelangelo used marble from Carrara, Italy, in a
number of sculptures.
Extremely pure calcite marble is used for most statues. Large
blocks of coloured 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 1 :
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.
Marble 2 :
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 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 spring 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 become 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.
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