Marble

The term marble in geology is restricted to metamorphic rocks in which the carbonate minerals have recrystallized. This process generally increases the average grain size, which gives marble its sparkling appearance. The word "marble" derives from the Greek (màrmaron) "crystalline rock", "shining stone”. The majority of marbles are dominated by calcite and/or dolomite (marbles dominated by dolomite are termed dolomarbles).

Marbles are formed by regional, and less commonly thermal, metamorphism of relatively pure limestone and dolomite, and in general, metamorphism of relatively pure limestone and dolomite yields generally phaneritic marble and dolomite marble, or dolomarble, respectively. Impure carbonate protoliths that contain variable amounts of quartz sand grains and shaly material may have, in addition to calcite and dolomite, quartz, diopside, tremolite, talc, phlogopite, wollastonite, calcic plagioclase, vesuvianite, forsterite, and grossular-andradite. Relict bedding may be preserved. Gray coloration, often uneven and streaked, in otherwise pure marbles is produced by minute specks of graphite or other minerals. But graphite and carbonaceous material can react with water under metamorphic conditions, liberating CO₂ and CH₄ that leaves the rock snow-white.

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Pure calcite marble, Fauske, Norway. From Sand atlas.

Coarse-grained calcitic marble from Leivset, Norway. From Sand atlas.

Dolomitic marble from Ahola, Finland. From Sand atlas.

Carrara marble quarry, Tuscany, Italy. From Dexmac.

Bibliography

• Bucher, K., & Grapes, R. (2011). Petrogenesis of metamorphic rocks. Springer Science & Business Media.
• Fossen, H. (2016). Structural geology. Cambridge University Press.
• Howie, R. A., Zussman, J., & Deer, W. (1992). An introduction to the rock-forming minerals (p. 696). Longman.
• Passchier, Cees W., Trouw, Rudolph A. J: Microtectonics (2005).
• Philpotts, A., & Ague, J. (2009). Principles of igneous and metamorphic petrology. Cambridge University Press.
• Shelley, D. (1993). Igneous and metamorphic rocks under the microscope: classification, textures, microstructures and mineral preferred-orientations.
• Vernon, R. H. & Clarke, G. L. (2008): Principles of Metamorphic Petrology. Cambridge University Press.
• Vernon, R. H. (2018). A practical guide to rock microstructure. Cambridge university press.

Photo
Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)	Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)	Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)
Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)	Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)	Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)
Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)	Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)	Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)
Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)	Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)	Termo-metamorphic marble (contact metamorphism). Campiglia Marittima, Livorno, Italy. XPL image, 1x (Field of view = 9mm)
Calcite and quartz crystals in a marble. XPL image, 2x (Field of view = 7mm)	Calcite and quartz crystals in a marble. XPL image, 2x (Field of view = 7mm)	Calcite and quartz crystals in a marble. XPL image, 2x (Field of view = 7mm)
Calcite and quartz crystals in a marble. XPL image, 2x (Field of view = 7mm)	Calcite and quartz crystals in a marble. XPL image, 2x (Field of view = 7mm)	Calcite and quartz crystals in a marble. XPL image, 2x (Field of view = 7mm)
Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)	Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)	Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)
Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)	Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)	Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)
Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)	Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)	Polygonal texture in a marble. XPL image, 2x (Field of view = 7mm)
Calcite crystals in a marble. XPL image, 10x (Field of view = 2mm)	Calcite crystals in a marble. XPL image, 10x (Field of view = 2mm)	Calcite crystals in a marble. XPL image, 10x (Field of view = 2mm)
Calcite crystals in a marble. XPL image, 10x (Field of view = 2mm)	Calcite crystals in a marble. XPL image, 10x (Field of view = 2mm)	Calcite crystals in a marble. XPL image, 10x (Field of view = 2mm)
Calcite crystals in a marble. XPL image, 2x (Field of view = 7mm)	Calcite crystals in a marble. XPL image, 2x (Field of view = 7mm)	Calcite crystal in a marble. XPL image, 10x (Field of view = 2mm)
Calcite crystal in a marble. XPL image, 10x (Field of view = 2mm)	Calcite crystal in a marble. XPL image, 10x (Field of view = 2mm)	Calcite crystal in a marble. XPL image, 10x (Field of view = 2mm)
Calcite crystal in a marble. XPL image, 10x (Field of view = 2mm)