Marble is a metamorphic rock composed of recrystallized carbonate minerals , most commonly calcite or dolomite.Marble may be foliated.Geologists use the term “marble” to refer to metamorphosed limestone;however ,stonemasons use the term more broadly to encompass unmetamorphosed limestone.Marble is commonly used for sculpture and as a building material.
Marble is a rock resulting from metamorphism of sedimentary carbonate rocks,most commonly limestone or dolomite rock.Metamorphism causes variable recrystallization of the original carbonate minerals grains.The resulting marble rock is typically composed of an interlocking mosaic of carbonate crystals.Primary sedimentary textures and structures of the original carbonate rock (protolith) have typically been modified or destroyed.
Pure white marble is the result of metamorphism of a very pure (silicate-poor) limestone or dolomite rock.The characteristics swirls and veins of many colored marble varieties are usually due to various minerals impurities such as clay,silt,sand,iron oxides,or chert which were originally present as grains or layers in the limestone.Green coloration is often due to serpentine resulting from originally magnesium-rich limestone or dolostone with silica impurities.These various impurities have been mobilized and recrystallized by the intense pressure and heat of the metamorphism.
White marble has been prized for its use in sculptures since classical times.This preference has to do with its softness,which made it easier to crave,relative isotropy and homogeneity,and a relative resistance to shattering.Also ,the low index of refraction of calcite allows light to penetrate several millimeters into the stone before being scattered out,resulting in the characteristics waxy look which gives “life” to marble sculptures of any kind,which is why many sculptors preferred and still prefer marble for sculpting.
Construction marble is a stone which is composed of calcite,dolomite or serpentine which is capable of taking a polish.More generally in construction,specifically the dimension stone trade, the term “marble” is used for any crystalline calcitic rock(and some non-calcitic rocks) useful as building stone.For example,Tennessee marble is really a dense granular fossiliferous gray to pink to marron Ordovician limestone that geologists call the Holston Formation.
Ashgabat,the capital city of Turkmenistan,was recorded in the 2013 Guinness Book of Records as having the world’s highest concentration of white marble buildings.
According to the United States Geological Survey,U.S. domestic marble production in 2006 was 46,400 tons valued at about $18.1 million,compared to 72,300 tons valued at $18.9 million in 2005.Crushed marble production (for aggregate and industrial uses) in 2006 was 11.8 million tons valued at $116 million,of which 6.5 million tons was finely ground calcium carbonate and the rest was construction aggregate.For comparison,2005 crushed marble production was 7.76million tons valued at $58.7 million,of which 4.8 million tons was finely ground calcium carbonate and the rest was construction aggregate.U.S.dimension marble demand is about 1.3 million tons.The DSAN World Demand for (finished) Marble Index has shown a growth China of 12% annually for the 2000-2006 period,compared to 10.5% annually for the 2000-2005 period.The largest dimension marble application is tile.
In 1998,marble production was dominated by 4 countries that accounted for almost half of world production of marble and decorative stone.Italy and China were the world leaders,each representing 16% of world production ,with Spain and India produced 9% and 8% respectively.Italy is the world leader in marble export, with 20% share in global marble production,followed by China with 16%,India with 10%,Spain with 6% and Portugal with 5%.
About Myanmar ( Htoo Han Thit's Hope For Myanma Marble )
In Myanmar has many quality marble deposite.Generally use as Buddha sculpture. Myanmar Marble also many kinds of colour and quality.Mandalay Region is famous of marble the best in quality compare with Europe.To extend export earning we hope to do.To get market from abroad know-how and idea shall be manage,we believed to obtain world market offer.