Difference between revisions of "Aragonite"

From CAMEO
Jump to navigation Jump to search
(3 intermediate revisions by 3 users not shown)
Line 10: Line 10:
 
calcium carbonate; nacre; shell white; coral; Aragonit (Deut., Pol.); aragonita (Esp.); aragonito (Esp.); aragonite (Fr., Port.); aragoniet (Ned.)
 
calcium carbonate; nacre; shell white; coral; Aragonit (Deut., Pol.); aragonita (Esp.); aragonito (Esp.); aragonite (Fr., Port.); aragoniet (Ned.)
  
[[[SliderGallery rightalign|Aragoniteitaly1.jpg~Raman|MFA- Aragonite.jpg~FTIR|aragonite.jpg~Chemical structure]]]
+
[[[SliderGallery rightalign|Aragonite 2.TIF~FTIR (MFA)|Aragonite (HU Min. Museum 116189), 50X, 785 nm copy.tif~Raman (MFA)|aragonite.jpg~Chemical structure]]]
  
 
== Other Properties ==
 
== Other Properties ==
Line 49: Line 49:
 
== Additional Information ==
 
== Additional Information ==
  
° R. Gettens, E. West Fitzhugh, R.Feller, "Calcium Carbonate Whites", ''Artists Pigments'', Vol. 2., A. Roy ed. Oxford University Press, Oxford, 1993. ° Mineralogy Database: [http://www.webmineral.com/data/Aragonite.shtml Aragonite]
+
° R. Gettens, E. West Fitzhugh, R.Feller, "Calcium Carbonate Whites", ''Artists Pigments'', Vol. 2., A. Roy ed. Oxford University Press, Oxford, 1993.  
 +
 
 +
° Mineralogy Database: [http://www.webmineral.com/data/Aragonite.shtml Aragonite]
  
 
== Additional Images ==
 
== Additional Images ==
Line 59: Line 61:
  
  
== Authority ==
+
== Sources Checked for Data in Record ==
  
 
* Jack Odgen, ''Jewellery of the Ancient World'', Rizzoli International Publications Inc., New York City, 1982
 
* Jack Odgen, ''Jewellery of the Ancient World'', Rizzoli International Publications Inc., New York City, 1982

Revision as of 09:53, 14 November 2019

1993.818-SC36608.jpg

Description

A crystalline form of Calcium carbonate that occurs in Coral, shells, pearls, stalactites, and water deposits. Aragonite was named after the Aragon region in Spain where it was first discovered. Its orthorhombic system forms compact, acicular crystals that make it harder and heavier than Calcite. When aragonite is formed by water deposition of calcium carbonate, the crystals often grow in radiating flowers. Aragonite mines are located in Europe, Bolivia, and the U.S. (New Mexico, Arizona). Aragonite was used in antiquity for beads and decorative items. It can be converted to calcite with heat (470 C) and changes slowly to calcite at room temperature.

36.178-20-3.jpg

Synonyms and Related Terms

calcium carbonate; nacre; shell white; coral; Aragonit (Deut., Pol.); aragonita (Esp.); aragonito (Esp.); aragonite (Fr., Port.); aragoniet (Ned.)

FTIR (MFA)

Aragonite 2.TIF

Raman (MFA)

Aragonite (HU Min. Museum 116189), 50X, 785 nm copy.tif

Chemical structure

Aragonite.jpg


Other Properties

Orthorhombic crystal system with platy or fibrous, acicular crystals that are often twinned. Reacts with acids to evolve carbon dioxide. Fluorescent. Brittle. Aragonite is harder and denser than calcite.

Luster = vitreous to resinous. Transparent to translucent. Fracture = subconchoidal. Streak = white

Strongly birefringent showing interference colors. Straight extinction

Composition CaCO3
CAS 471-34-1
Mohs Hardness 3.5 - 4.0
Density 2.93-2.95
Molecular Weight mol. wt. = 100.09
Refractive Index 1.530, 1.682, 1.686

Hazards and Safety

No significant hazards.

Mallinckrodt Baker: MSDS

Additional Information

° R. Gettens, E. West Fitzhugh, R.Feller, "Calcium Carbonate Whites", Artists Pigments, Vol. 2., A. Roy ed. Oxford University Press, Oxford, 1993.

° Mineralogy Database: Aragonite

Additional Images


Sources Checked for Data in Record

  • Jack Odgen, Jewellery of the Ancient World, Rizzoli International Publications Inc., New York City, 1982
  • Nicholas Eastaugh, Valentine Walsh, Tracey Chaplin, Ruth Siddall, Pigment Compendium, Elsevier Butterworth-Heinemann, Oxford, 2004 Comment: Refractive Index: alpha=1.529-1.530; beta=1.680-1.682; gamma=1.685-1.686
  • C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
  • G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 131
  • Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
  • Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
  • Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
  • The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998

Retrieved from "https://cameo.mfa.org/index.php?title=Aragonite&oldid=65028"