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Lime Stone
Limestone is typically formed over many years at the bottom of oceans or lakes from the accumulation of shells, bones and other calcium rich goods. The calcium in the bones & shells combines with Carbon Dioxide in the water to boom Calcium Carbonate which is the basic mineral structure of all Limestone Limestone are typically used for flooring, wall cladding, vanity tops etc.
Limestone is essentially a Dolomite stone, it shows high resistance in freezing and thawing conditions, which indicate that it can be used in any atmospheric condition without getting affected. Compressive strength of Limestone is 30,000 lbs./ sq. inch, which is the highest strength among the available stone category and can carry a suitable load.
Limestone is a sedimentary rock composed largely of the
mineral calcite (calcium carbonate: CaCO3). Limestone
often contains variable amounts of silica in the form of chert or flint, as well as varying amounts of clay, silt
and sand as disseminations, nodules, or layers within the
rock. The primary source of the calcite in limestone is
most commonly marine organisms. These organisms secrete
shells that settle out of the water column and are
deposited on ocean floors as pelagic ooze or alternatively
is conglomerated in a coral reef (see lysocline for
information on calcite dissolution). Secondary calcite may
also be deposited by supersaturated meteoric waters
(groundwater that precipitates the material in caves).
This produces speleothems such as stalagmites and
stalactites. Another form taken by calcite is that of
oolites (oolitic limestone) which can be recognised by its
granular appearance. Limestone makes up about 10% of the
total volume of all sedimentary rocks.
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Limestone landscape
Limestone is partially soluble, especially in acid, and
therefore forms many erosional landforms. These include
limestone pavements, pot holes, cenotes, caves and gorges.
Such erosion landscapes are known as karsts. Limestone is
less resistant than most igneous rocks, but more resistant
than most other sedimentary rocks. Limestone is therefore
usually associated with hills and downland and occurs in
regions with other sedimentary rocks, typically clays.
Bands of limestone emerge from the Earth's surface in
often spectacular rocky outcrops and islands. Examples
include the Burren in Co. Clare, Ireland; the Verdon Gorge
in France; Malham Cove in North Yorkshire and the Isle of
Wight[1], England; on Fårö near the Swedish island of
Gotland, the Niagara Escarpment in Canada/USA, Notch Peak
in Utah, and the Ha Long Bay National Park in Vietnam.
Unique habitats are found on alvars, extremely level
expanses of limestone with thin soil mantles. The largest
such expanse in Europe is the Stora Alvaret on the island
of Oland, Sweden.
Huge quarries in northwestern Europe, such as those of
Mount Saint Peter (Belgium/Netherlands), extend for more
than a hundred kilometers.
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Uses of limestone
Limestone is especially popular in architecture, and many
landmarks around the world, especially in North America
and Europe, are made primarily of the material. So many
buildings in Kingston, Ontario, Canada were constructed
from it that it is nicknamed the 'Limestone City'.
Limestone is readily available and relatively easy to cut
into blocks or more elaborate carving. It is also
long-lasting and stands up well to exposure. However, it
is a very heavy material, making it impractical for tall
buildings. It is also quite expensive.
Limestone was most popular in the early 20th and late 19th
centuries. Train stations, banks and other structures from
that era are normally made of limestone. Limestone is used
as a facade on some skyscrapers, but only in thin plates
for covering rather than solid blocks. In the United
States, Indiana, most notably the Bloomington area, has
long been a source of high quality quarried limestone,
called Indiana limestone.[2] Many famous buildings in
London are built from Portland limestone.
Limestone was also a very popular building block in the
middle ages in the areas where it occurred since it is
hard, durable, and commonly occurs in easily accessible
surface exposures. Many medieval churches and castles in
Europe are made of limestone. Beer stone was a popular
kind of limestone for medieval buildings in southern
England.
Limestone and marble are very reactive to acid solutions,
making acid rain a significant problem. Many limestone
statues and building surfaces have suffered severe damage
due to acid rain. Acid-based cleaning chemicals can also
etch limestone, which should only be cleaned with a
neutral or mild alkaline-based cleaner.
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Granite