Stilpnomelane Marble

The word "marble" derives from the Greek (mármaron) "crystalline rock", "shining stone”. A marble is a generic term for a metamorphosed rock dominated by carbonate minerals. The majority of marbles are dominated by calcite and/or dolomite. Marbles dominated by dolomite are termed dolomarbles. Common accessory minerals include quartz, diopside, tremolite, talc, phlogopite, wollastonite, calcic plagioclase, vesuvianite, forsterite, and grossular-andradite garnet.

Marbles are formed by regional, and less commonly thermal, metamorphism of relatively pure limestone and dolomite. Impure limestones, containing chert, quartz sand, and/or argillaceous materials contain the silicate minerals listed above and are usually termed calc-silicate rocks. Often calc-silicate is used as a prefix for another metamorphic rock type, for example, calc-silicate schist, to indicate the presence of significant carbonates.

Bibliography

• David Shelley (1983): Igneous and metamorphic rocks under the microscope. Campman & Hall editori.
• E. WM. Heinrich (1956): Microscopic Petrografy. Mcgraw-hill book company,inc
• Anthony R. Phillpotts & Jay J. Ague: Principles of igneous and metamorphic petrology. Cambridge editore.
• Passchier, Cees W., Trouw, Rudolph A. J: Microtectonics (2005)

Photo
Stilpnomelane crystals in a Marble. PPL image, 2x (Field of view = 7mm)	Stilpnomelane crystals in a Marble. PPL image, 2x (Field of view = 7mm)	Stilpnomelane crystals in a Marble. PPL image, 2x (Field of view = 7mm)
Stilpnomelane crystals in a Marble. PPL image, 10x (Field of view = 2mm)	Stilpnomelane crystals in a Marble. XPL image, 10x (Field of view = 2mm)	Stilpnomelane crystals in a Marble. XPL image, 10x (Field of view = 2mm)
Stilpnomelane crystals in a Marble. XPL image, 10x (Field of view = 2mm)	Stilpnomelane crystals in a Marble. PPL image, 10x (Field of view = 2mm)	Stilpnomelane crystals in a Marble. PPL image, 10x (Field of view = 2mm)
Stilpnomelane crystals in a Marble. PPL image, 10x (Field of view = 2mm)	Stilpnomelane crystals in a Marble. PPL image, 10x (Field of view = 2mm)