Is Marble A Silicate

Width of sample 11 cm.

Is marble a silicate. Clay minerals within the marble will alter to micas and more complex silicate structures as the level of metamorphism increases. Is an ingredient in ceramics paint and roofing material. Marble that has been exposed to low levels of metamorphism will have very small calcite crystals. And is a main ingredient in many cosmetics.

Bands of calc silicate rock may alternate with bands of marble or form nodules and patches sometimes producing interesting decorative effects but these rocks are particularly difficult to finish because of the great difference in hardness between the silicates and carbonate minerals. 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. Talc is a clay mineral composed of hydrated magnesium silicate with the chemical formula mg 3 si 4 o 10 oh 2 talc in powdered form often combined with corn starch is used as baby powder this mineral is used as a thickening agent and lubricant. Often mistaken for marble is serpentine which is actually magnesium silicate based as opposed to calcite based.

It has been subjected to granulite grade metamorphism at temperatures reaching 800 c and depths of around 30 km during the laxfordian orogeny. As a result of the different mineralogy and whole rock chemistry of serpentine it exhibits greater acid resistance and abrasion resistance than does a true marble. Marble is a metamorphic rock formed when limestone is subjected to high pressure or heat. However mostly because of marketing reasons some coarse grained limestones grainstones and dolomites are also sold as marble.

The marble lens is 5 m thick and 50 m long and is situated in the nose of a minor fold that is parasitic on the early isoclinal closure in the potassic felsic schist unit. This process generally increases the average grain size which gives marble its sparkling appearance. Albitite is a hydrothermal metasomatic rock that may superficially resemble marble but it is composed of silicate feldspar group mineral albite. Calc silicate marble the term marble in geology is restricted to metamorphic rocks in which the carbonate minerals have recrystallized.

The crystals become larger as the level of metamorphism progresses. The characteristic swirls and veins of many colored marble varieties are usually due to various mineral impurities such as clay silt sand iron oxides or chert which were originally present as grains or layers in the limestone. Pure white marble is the result of metamorphism of a very pure silicate poor limestone or dolomite protolith.