Dolomite

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Egyptian vessel
MFA# 01.7287

Description

A pearly sedimentary mineral composed of calcium-magnesium carbonate. that was first described in 1791 by the French naturalist Deodat de Dolomieu in the Dolomite mountains in Italy. Domolite rock is hard, crystalline, carbonaceous stone with high percentage (90 % to 100 %) of the mineral dolomite. It is found in ledge formations throughout Europe (Saxony, Switzerland, Italy, France, Spain, Greece), South America (Brazil) and the United States (Vermont, New York, Pennsylvania, North Carolina, Illinois, Missouri). Although usually a translucent white in color, the mineral dolomite varies widely to yellow, pink, green, brown and gray. Iron is often a minor component replacing some of the Magnesium. Dolomite rock has been and is currently used as a building stone, in furnace linings, in ceramics, and as a Filler in Paper. Under high temperatures and pressures, dolomite is metamorphosed into Dolomitic marble.

Stone Corral Formation dolomite

Synonyms and Related Terms

calcium magnesium carbonate; magnesium calcium carbonate; Dolomit (Deut.); dolomita (Esp.); dolomie (Fr.); dolomiet (Ned.); dolomite (Port.); bitter spar; pearl spar; dolomitic marble

Physical and Chemical Properties

FTIR (MFA)

Dolomite.TIF

Raman (MFA)

Dolomite marble, 50X, laser 532 nm copy.tif

  • Hexagonal crystal systems with rhombohedral habits.
  • Cleavage is parallel to the rhombohedron; perfect in three directions.
  • Fracture = subconchoidal.
  • Luster = vitreous to pearly.
  • Streak = white.
  • Under cross polars has high birefringence with strong interference colors
  • Dissolves slowly in dilute cold hydrochloric acid with effervescence.
Composition CaMg(CO3)2
Mohs Hardness 3.5 - 4.0
Density 2.8-2.9 g/ml
Refractive Index w=1.679; e=1.500

Additional Images

Resources and Citations

  • José Delgado Rodrigues, LNEC, Submitted information, 2009.
  • Nicholas Eastaugh, Valentine Walsh, Tracey Chaplin, Ruth Siddall, Pigment Compendium, Elsevier Butterworth-Heinemann, Oxford, 2004 Comment: Refractive index: w=1.679; e=1.500
  • Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
  • Anne Grimmer, Glossary of Building Stone Terms, A Glossary of Historic Masonry Deterioration Problems and Preservation Treatments, National Park Service, Washington DC, 1984
  • C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
  • Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
  • Thomas Gregory, The Condensed Chemical Dictionary, Reinhold Publishing, New York, 3rd ed., 1942
  • G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 273
  • Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
  • Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
  • Susan E. Schur, Conservation Terminology: A review of Past & Current Nomenclature of Materials, Technology and Conservation, Spring (p.34-39); Summer (p.35-38); Fall (p.25-36), 1985