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Aragonite

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Formula:
CaCO
 
3
System:OrthorhombicColour:Colorless to white or ...
Lustre:Vitreous, ResinousHardness:3½ - 4
Member of:Aragonite Group
Name:Named in 1797 by Abrahan Gottlieb Werner for the type locality, the village of Molina de Aragón, Spain, and not the province of Aragón, a mistake made by several later writers.
Polymorph of:Calcite, Vaterite


Aragonite Group.

The principal member of the Aragonite Group, aragonite is the second most common polymorph of natural calcium carbonate (the most common is calcite). It is significantly less widespread and abundant than calcite and is formed under a much narrower range of physio-chemical conditions. It is metastable relative to calcite and often converts to calcite accompanying changes in environment. It is nearly always a low-temperature, near surface mineral.

Visit gemdat.org for gemological information about Aragonite. Currently in public beta-test.

Classification of Aragonite

IMA status:Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Strunz 8th edition ID:5/B.04-10
Nickel-Strunz 10th (pending) edition ID:5.AB.15

5 : CARBONATES (NITRATES)
A : Carbonates without additional anions, without H2O
B : Alkali-earth (and other M2+) carbonates
Dana 7th edition ID:14.1.3.1
Hey's CIM Ref.:11.4.2

11 : Carbonates
4 : Carbonates of Ca
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Type Occurrence of Aragonite

Type Locality:Gallo river, Molina de Aragón, Guadalajara, Castile-La Mancha, Spain
Year of Discovery:1797

Occurrences of Aragonite

Geological Setting:As speleothemes in limestone caves; as pisolites, sinters and massive lamellar deposits at geysers and hot springs; as seafloor oolites; with siderite in iron deposits; with calcite and dolomite and other magnesium minerals in altered serpentinites, dunites and peridotites; and as a replacement mineral in various rock types and ore deposits, formed from low-temperature and pressure aqueous solutions.

Physical Properties of Aragonite

Lustre:Vitreous, Resinous
Diaphaneity (Transparency):Transparent, Translucent
Colour:Colorless to white or grey, often stained various hues by impurities, such as blue, green, red or violet; colourless in transmitted light.
Streak:Uncolored/white.
Hardness (Mohs):3½ - 4
Hardness Data:Measured
Tenacity:Brittle
Cleavage:Distinct/Good
On {010} distinct; On {110} and {011} very indistinct.
Fracture:Sub-Conchoidal
Density (measured):2.947 g/cm3
Density (calculated):2.944 g/cm3

Crystallography of Aragonite

Crystal System:Orthorhombic
Class (H-M):mmm (2/m 2/m 2/m) - Dipyramidal
Cell Parameters:a = 4.95Å, b = 7.96Å, c = 5.74Å
Ratio:a:b:c = 0.622 : 1 : 0.721
Unit Cell Volume:V 226.17 ų (Calculated from Unit Cell)
Z:4
Morphology:Short to long prismatic [100], sometimes flattened {010}; acicular, often with steep pyramidal or domatic terminations; or tabular {001}; also stalactic, columnar, in stellate or radiating aggregates, and fibrous crusts of tiny acicular crystals.
Twinning:Single crystals are typically twinned cyclically on {110} producing pseudo-hexagonal aggregates of contact and penetration twins. Polysynthetic twinning produces lamellae or fine striations parallel to [100].
Crystal Atlas:
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Aragonite no.1 - Goldschmidt (1913-1926)
Aragonite no.5 - Goldschmidt (1913-1926)
Aragonite no.36 - Goldschmidt (1913-1926)
Aragonite no.37 - Goldschmidt (1913-1926)
Aragonite no.55 - Goldschmidt (1913-1926)
Aragonite no.109 - Goldschmidt (1913-1926)
Aragonite no.112 - Goldschmidt (1913-1926)
Aragonite no.197 - Goldschmidt (1913-1926)
Aragonite no.238 - Goldschmidt (1913-1926)

About Crystal Atlas

The mindat.org Crystal Atlas allows you to view a selection of crystal drawings of real and idealised crystal forms for this mineral and, in certain cases, 3d rotating crystal objects. The 3d models and HTML5 code are kindly provided by www.smorf.nl.

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Structure
  Reference
Dal Negro A Ungaretti L (1971) Refinement of the crystal structure of aragonite. American Mineralogist 56:768-772.

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More Crystal Structures
Click here to view more crystal structures at the American Mineralogist Crystal Structure Database
Epitaxi Comments:Mutual orientation in certain calcite pseudomorphs after aragonite. Also in aragonite pseudomorphs after gypsum, with aragonite {010}[001] parallel to the gypsum {010}[001].
X-Ray Powder Diffraction:
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Radiation - Copper Kα
Data Set:
Horizontal Axis: ° to ° Vertical Axis: % Source Data: Filtered Data:
Data courtesy of RRUFF project at University of Arizona, used with permission.
X-Ray Powder Diffraction:
d-spacingIntensity
3.40(100)
3.27(50)
2.70(60)
2.48(40)
2.37(50)
2.34(30)
2.33(30)
1.977(60)

Optical Data of Aragonite

Type:Biaxial (-)
RI values: nα = 1.529 - 1.530 nβ = 1.680 - 1.682 nγ = 1.685 - 1.686
2V:Measured: 18° to 19°, Calculated: 16° to 18°
Maximum Birefringence:δ = 0.156

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:High
Dispersion:weak

Chemical Properties of Aragonite

Formula:
CaCO
 
3
Simplified for copy/paste:CaCO3
Essential elements:C, Ca, O
All elements listed in formula:C, Ca, O
CAS Registry number:471-34-1

CAS Registry numbers are published by the American Chemical Society
Common Impurities:Sr,Pb,Zn

Relationship of Aragonite to other Species

Member of:Aragonite Group
Other Members of Group:

- +
Cerussite
PbCO
 
3
Strontianite
SrCO
 
3
Witherite
BaCO
 
3
Common Associates:
SulphurSmithsoniteSideriteMalachiteLimonite
HydromagnesiteGypsumDolomiteClayCerussite
CelestineCalciteBrucite
Related Minerals - Nickel-Strunz Grouping):

- +
5.AB.05Calcite
CaCO
 
3
5.AB.05Gaspéite
(Ni,Mg,Fe)CO
 
3
5.AB.05Magnesite
MgCO
 
3
5.AB.05Otavite
CdCO
 
3
5.AB.05Rhodochrosite
MnCO
 
3
5.AB.05Siderite
FeCO
 
3
5.AB.05Smithsonite
ZnCO
 
3
5.AB.05Spherocobaltite
CoCO
 
3
5.AB.10Ankerite
Ca(Fe
2+
 
,Mg)(CO
 
3
)
 
2
5.AB.10Dolomite
CaMg(CO
 
3
)
 
2
5.AB.10Kutnohorite
Ca(Mn,Mg,Fe)(CO
 
3
)
 
2
5.AB.10Minrecordite
CaZn(CO
 
3
)
 
2
5.AB.15Cerussite
PbCO
 
3
5.AB.15Strontianite
SrCO
 
3
5.AB.15Witherite
BaCO
 
3
5.AB.20Vaterite
CaCO
 
3
5.AB.25Huntite
CaMg
 
3
(CO
 
3
)
 
4
5.AB.30Norsethite
BaMg(CO
 
3
)
 
2
5.AB.35Alstonite
BaCa(CO
 
3
)
 
2
5.AB.40Olekminskite
Sr(Sr,Ca,Ba)(CO
 
3
)
 
2
5.AB.40Paralstonite
BaCa(CO
 
3
)
 
2
5.AB.45Barytocalcite
BaCa(CO
 
3
)
 
2
5.AB.50Carbocernaite
(Ca,Na)(Sr,Ce,Ba)(CO
 
3
)
 
2
5.AB.55Benstonite
(Ba,Sr)
 
6
(Ca,Mn)
 
6
Mg(CO
 
3
)
 
13
5.AB.60Juangodoyite
Na
 
2
Cu(CO
 
3
)
 
2
Related Minerals - Hey's Index Grouping:

- +
11.4.1Calcite
CaCO
 
3
11.4.3Vaterite
CaCO
 
3
11.4.4Monohydrocalcite
CaCO
 
3
· H
 
2
O
11.4.5Ikaite
CaCO
 
3
· 6H
 
2
O
11.4.6Dolomite
CaMg(CO
 
3
)
 
2
11.4.7Huntite
CaMg
 
3
(CO
 
3
)
 
4
11.4.8Sergeevite
Ca
 
2
Mg
 
11
(CO
 
3
)
 
13
· 10H
 
2
O

Other Names for Aragonite

Synonyms:
ArragoniteArragon SparChimboraziteConchiteCtypeite
IgliteIgloiteKtypéiteOserskitePisa Carolina
Stillatitius lapisWinnieite
Other Languages:
Aragonese:Aragonito
Bosnian (Latin Script):Aragonit
Bulgarian:Арагонит
Catalan:Aragonita
Czech:Hrachovec
Vřídlovec
Dutch:Aragoniet
Esperanto:Aragonito
Estonian:Aragoniit
Finnish:Aragoniitti
French:Aragonite
Galician:Aragonita
German:Aragonit
Arragonischer Apatit
Arragonischer Kalkspath
Arragonit
Brudelstein
Carlsbader Erbsen
Carlsbader Pisolith
Carls-Erbsen
Chimborazit
Conchit
Excentrischer Kalkstein
Iglit
Igloit
Ktypéit
Nadelstein
Oserskit
Prismatisches Kalkhaloid
Schallenkalk
Sprudelstein
Walstein
Winnieit
Hebrew:ארגוניט
Hungarian:Aragonit
Italian:Aragonite
Japanese:アラレ石
霰石
Latin:Aragonite
Marmoreus ramulosus
Spathum prismaticum in igne lucem spargens
Lithuanian:Aragonitas
Lojban:Globuli tophacei
Low Saxon:Aragonit
Polish:Aragonit
Portuguese:Aragonita
Romanian:Aragonit
Russian:Арагонит
Serbian (Cyrillic Script):Арагонит
Simplified Chinese:霰石
文石
Slovak:Aragonit
Spanish:Aragonito
Arragonita
Chimborazita
Conchita
Iglita
Igloita
Ktypéita
Oserskita
Winnieita
Tamil:அரகோனைட்
Traditional Chinese:霰石
文石
Ukrainian:Арагоніт
Vietnamese:Aragonit
Varieties:
Aragonite Satin SparFlos FerriPlumboan AragoniteStrontian AragoniteTarnowitzite
Zincian Aragonite

Other Information

Fluorescence in UV light:Pale rose, yellow, white or bluish, with greenish or white phosphorescence (LW UV); yellowish (SW UV).
Thermal Behaviour:Begins to convert to calcite at about 400° when heated in dry air.

Thermoluminescent.
Other Information:Readily soluble in dilute acids with effervescence.
Health Warning:No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
External LinksSearch for toxicity information at the United States National Library of Medicine

References for Aragonite

Reference List:

- +
Davila, M. (1767) Catalogue syst. et raisonné des curiosités de la nature et de l’art qui composent de cabinet de M. Davila. 3 volumes, Paris: 2: 50, 52.

Linnaeus (1768) Systema Naturae of Linnaeus: 183 (as Stalactites Flos ferri; Marmoreus ramulosus).

Klaproth (1788) Bergmaaennusches Journal, Freiberg (Neues Bergmannische Journal): 1: 299.

Klaproth (1788) Crell’s Chemical Journal, London: 1: 387 (as carbonate of lime).

Werner (1788) Bergmaaennusches Journal, Freiberg (Neues Bergmannische Journal): 1: 95 (as Arragonischer Apatit).

Born, I. von (1790) Catalogue méthodique et raisonné de la collection des fossils de Mlle. Eleonore de Raab. 4 volumes, Vienna: 2: 320.

Werner (1790) Bergmaaennusches Journal, Freiberg (Neues Bergmannische Journal): 2: 74 (as Arragonischer Kalkspath.

Gmelin (1793) Linnaei Syst. Nat., 13th edition: 3: 92.

Kirwan, R. (1794) Elements of Mineralogy. (1784), second edition, London: 1: 87 (as Arragon Spar).

Esmark (1798) Bergmaaennusches Journal, Freiberg (Neues Bergmannische Journal): 3: 99.

Karsten, D.L.G. (1800) Mineralogische Tabellen, Berlin. First edition: 34, 74 (as Excentrischer Kalkstein)

Haüy, R.J. (1801) Traité de minéralogie. First edition: in 4 volumes with atlas in fol. Paris: vol. 2.

Emmerling, L.. (1802) Lehrbuch der Mineralogie, 2nd. Edition, Giessen: 2: 684 (as Arragonit).

Stromeyer (1813) Annalen der Physik, Halle, Leipzig.

Clarke (1821) Annals of Philosophy, London: 2: 57, 147 (as Chimborazite).

Rose (1853) Annalen der Physik, Halle, Leipzig: 91: 147.

Sénarmont (1854) Annales de chimie et de physique, Paris: 41[3]: 61.

Leydolt (1856) Konigliche Akademie der Wissenschaften, Vienna, Sitzber.: 19: 10.

Rose (1856) Akademie der Wissenschaften, Berlin, Abh.: 64, 66.

Rose (1856) Annalen der Physik, Halle, Leipzig: 97: 161.

Luca (1858) Nuovo Cimento, Pisa: 7: 453.

Scharff (1861) Neues Jahrbuch für Mineralogie, Geologie und Paleontologie, Heidelberg, Stuttgart: 31.

Forbes (1862) Quart. J. Geol. Soc.: 17: 45

Breithaupt (1865) Berg.- und hüttenmännisches Zeitung, Freiberg, Leipzig (merged into Glückauf): 24: 319.

Sandberger (1866) Annalen der Physik, Halle, Leipzig: 129: 472.

Koksharov, N. von (1870) Materialien zur Mineralogie Russlands. 11 volumes with atlas: vol. 6: 261.

Schrauf (1870) Konigliche Akademie der Wissenschaften, Vienna, Sitzber.: 62[2]: 734.

Roepper analysis in: Genth (1875) Second Geological Survey, Pennsylvania, Report: 163.

Geinitz (1876) Neues Jahrbuch für Mineralogie, Geologie und Paleontologie, Heidelberg, Stuttgart: 449.

Lasaulx (1879) Neues Jahrbuch für Mineralogie, Geologie und Paleontologie, Heidelberg, Stuttgart: 505.

Domeyko (1881) Annales des mines: 18[7]: 531.

Kalkowsky (1884) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 9: 497.

Traube (1884) Inaugural Dissertation, Greifswald.

Bauer (1886) Neues Jahrbuch für Mineralogie, Geologie und Paleontologie, Heidelberg, Stuttgart: I: 72, 79.

Beckenkamp (1888) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 14: 375.

Mülheim (1888) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 14: 229.

Traube (1889) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 15: 410.

Bauer (1890) Neues Jahrbuch für Mineralogie, Geologie und Paleontologie, Heidelberg, Stuttgart: I: 12.

Offret (1890) Bulletin de la Société française de Minéralogie: 13: 582.

Lemberg (1892) Zeitschrift der Deutsche geologische Gesellschaft, Berlin: 44: 232.

Jeremejev (1897) Bulletin de Académy imperial de sciences, St. Pétersburg: 7, no. 1.

Keilhack (1898) Zeitschrift der Deutsche geologische Gesellschaft, Berlin: 50: 131.

Lacroix (1898) Comptes rendus de l’Académie des sciences de Paris: 126: 602.

Vater (1899) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 31: 575.

Beckenkamp (1900) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 32: 25.

Brauns (1901) Centralblatt für Mineralogie, Geologie und Paleontologie, Stuttgart: 134.

Meigen (1901) Centralblatt für Mineralogie, Geologie und Paleontologie, Stuttgart: 577.

Mügge (1901) Jb. Min., Beil.-Bd.: 14: 246.

Wyrouboff (1901) Bulletin de la Société française de Minéralogie: 24: 371.

Panebianco (1902) Rivista di mineralogia e cristallografia italiana, Padua: 28: 5.

Vater (1902) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 35: 149.

Mügge (1903) Jb. Min., Beil.-Bd.: 16: 379.

Lacroix, A. (1909): 3: 670.

Thugutt (1910) Centralblatt für Mineralogie, Geologie und Paleontologie, Stuttgart: 786.

Wetzel (1910) Neues Jahrbuch für Mineralogie, Geologie und Paleontologie, Heidelberg, Stuttgart: II: 70.

Doelter, C. (1911) Handbuch der Mineral-chemie (in 4 volumes divided into parts): 1: 337.

Butler (1913) Economic Geology: 8: 8 (Zn-aragonite).

Goldschmidt, V. (1913) Atlas der Krystallformen. 9 volumes, atlas, and text: vol. 1: 90.

Quercigh (1915) Reale accademia nazionale dei Lincei, Rome, Rend.: 24[5]: 1231.

Watanabe (1915) Beiträge zur Mineralogie von Japan, Tokyo: no. 5: 237.

Johnson, Merwin, and Wlliamson (1916) American Journal of Science: 41: 473.

Schäfer and Schubert (1916) Annalen der Physik, Halle, Leipzig: 50: 283.

Barca (1919) Mus. Nac. Cien. Nat. Trab. Madrid, Ser. Geol., no. 24.

Buttenbach (1919) Ann. Soc. geol.. Belgique: 42: 93.

Krüger (1922) Ak. Leipzig, Sitzber.: 74: 253.

Stevanović (1922) Ann. géol. pénin. Balkan: 7: 85 [Min. Abs. (1923): 2: 116].

Veit (1922) Jb. Min., Beil.-Bd.: 45: 121.

Bragg (1924) Proceedings of the Royal Society of London: 105: 16; 105A: 370.

Tomkeieff (1925) Mineralogical Magazne: 20: 408.

Wyckoff (1925) American Journal of Science: 9: 145.

Hintze, Carl (1926) Handbuch der Mineralogie. Berlin and Leipzig. 6 volumes: 1[3A]: 2974, 3019.

Shannon (1926) U.S. National Museum Bull. 131: 237.

Vendl (1926) Hist. Nat. Mus. Natl. Hung.: 24: 223.

Yamaguchi (1927) Journal of the Geological Society of Tokyo: 34: 159.

Voigt, Woldemar (1928) Lehrbuch der Kristallphysik. 978 pp., Leipzig.

O'Daniel (1930) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 74: 333.

Köhler (1931) Chemie Erde: 6: 257.

Obenauer (1931) Jahrbuch Min., Beil.-Bd.: 64: 437.

Reichert (1932) Földtani Közlöny, Budapest (Magyarhone Földtani Torsulat): 62: 196.

Shoji (1932) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 84: 74.

Köhler and Leitmeier (1934) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 87: 146.

Kôzu and Kani (1934) Proceedings of the Imperial Academy, Tokyo: 10: 222.

Krejci-Graff (1934) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 88: 260.

Leitmeier and Feigl (1934) Mineralogische und petrographische Mitteilungen, Vienna: 45: 447.

Gagarin (1936) Ann. géol. pénin. Balkan: 13: 72.

Heritsch (1936) Zentralblatt Mineralien: 33.

Hutton (1936) Transactions of the Royal Society of New Zealand: 66: 35.

Siegl (1936) Mineralogische und petrographische Mitteilungen, Vienna: 48: 286.

Rottenbach (1937) Inaugural Dissertation, Bonn.

Tokody (1937) Hist. Nat. Mus. Natl. Hung.: 31: 171.

Chudoba and Rottenbach (1938) Zentralblatt Mineralien: 261.

Seifert (1938) Zeitschrift für Kristallographie, Mineralogie und Petrographie, Leipzig: 100: 120.

Alexander (1940) American Journal of Science: 238: 366.

Haberlandt (1940) Chemie der Erde, Jena: 13: 212.

Kleber (1940) Neues Jahrbuch für Mineralogie, Geologie und Paleontologie, Beil.-Bd., Heidelberg, Stuttgart: 75: 465.

Alexander (1941) Gemmologist: 10: 93.

Alexander (1941) Science: 93: 110.

Yugovics (1941) Földtani Közlöny, Budapest (Magyarhone Földtani Torsulat): 71: 23.

Andrew and Schaller (1942) American Mineralogist: 27: 135.

Melmore (1942) Nature: 150: 382.

Bray (1945) Journal of the Royal Society of new South Wales: 78: 113.

Hugi (1945) Schweizerische mineralogische und petrographische Mitteilungen, Frauenfeld: 25: 114.

Zavaritzky (1948) Doklady of the Academy of Sciences of the USSR, Earth Science Sections: 63: 725.

Faust (1950) American Mineralogist: 35: 207.

Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Etc. John Wiley and Sons, Inc., New York, 7th edition, revised and enlarged: 182-193.

American Mineralogist (1971): 56: 758-772.

Gaines, Richard V., H. Catherine, W. Skinner, Eugene E. Foord, Brian Mason, Abraham Rosenzweig (1997), Dana's New Mineralogy : The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, 8th. edition: 442.

Reviews in Mineralogy, Mineralogical Society of America: 11.

Internet Links for Aragonite

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  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Aragonite details from Handbook of Mineralogy (PDF)
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    Localities for Aragonite

    The map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
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