Primary Minerals In Limestone And Marble

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Primary minerals in limestone and marble. Marble and limestone lie at the opposite end of the hardness scale from granite. Marble is a metamorphic rock composed of recrystallized carbonate minerals most commonly calcite or dolomite marble is typically not foliated although there are exceptions in geology the term marble refers to metamorphosed limestone but its use in stonemasonry more broadly encompasses unmetamorphosed limestone. While marble is slightly harder and denser than limestone both rate very low on the mohs scale a rating used to measure the hardness of stones. Marble is a metamorphic rock formed when limestone is subjected to high pressure or heat.

Limestone generally ranks at around a 3 on the scale while marble falls between 3 and 4. Limestone blocks were the primary construction material used in many of the pyramids of egypt and latin america. The primary difference between limestone and marble is that marble is an example of metamorphic rock while limestone is an example of sedimentary rock. Modern construction uses calcite in the form of limestone and marble to produce cement and concrete.

In its pure form marble is a white stone with a crystalline and sugary appearance consisting of calcium carbonate caco 3 usually marble contains other minerals including quartz graphite pyrite and iron oxides these minerals can give marble a pink brown gray green or variegated coloration. It is composed primarily of the mineral calcite caco 3 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. Typically marble is composed of the following major constituents. Limestone composed of silica clay silt and sand limestone comes in a variety of colors and may have a crystalline clastic granular or massive finish.

Marble is commonly used for sculpture and as a building material. Even though their chemical nature is almost similar to each other there are many differences between limestone and marble in the way they originate and the physical characteristics they possess. The main difference between limestone and marble is that limestone is a sedimentary rock typically composed of calcium carbonate fossils and marble is a metamorphic rock. Both limestone and marble are types of rock made of calcium carbonate residues.

The exact chemical composition of marble will greatly vary dependong on the location and the minerals or impurities present in the limestone during recrystallization. Limestone forms when shells sand and mud are deposited at the bottom of oceans and lakes and over time solidify into rock. Marble is a metamorphic rock that forms when limestone is subjected to the heat and pressure of metamorphism.