Donate now to keep mindat.org alive!Help mindat.org|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on Mindat
The most common minerals on earthMineral PhotographyThe Elements and their Minerals
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralSearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsMember ListBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Andalusite

This page is currently not sponsored. Click here to sponsor this page.
Formula:
Al2(SiO4)O
Colour:
Pink to red brown, occasionally yellow, green, white, gray rarely violet
Lustre:
Vitreous, Sub-Vitreous, Greasy
Hardness:
6½ - 7½
Specific Gravity:
3.13 - 3.21
Crystal System:
Orthorhombic
Name:
Named by Jean-Claude Delamétherie in 1798 for the supposed type locality, "Andalusia region", Spain, although he seems to have been not very familiar with Spanish geography and the type locality is not in Andalusia.

Andalusite was first analysed by Werner on specimens coming from Spain. Both Werner and Delamétherie believed that the specimens came from Andalusia, which is why the latter named it "andalusite". However, it seems that the analyzed specimens came from El Cardoso (Guadalajara), a town they erroneously thought to be in Andalusia. Consequently, the type locality must be considered El Cardoso, probably the outcrop located in Zahurdon. The error was perpetuated by other later authors, who considered that the origin was the province of Almeria, and remained so in the majority of books, even in modern ones. Furthermore, andalusite had already been known previously and had even been described, in its chiastolite variety, by a Spanish author, Torrubia, in 1754. The description was published in a famous book, "Aparato para la Historia Natural Española", in which aragonite also appears. In both cases, the descriptions are accompanied by illustrations that depict both minerals unmistakably. (See the article by Dr. Miguel Calvo, "Minerales que tienen en España su localidad tipo" - http://milksci.unizar.es/miner/mineralesp/tipo.html)
Polymorph of:
Isostructural with:
Hide all sections | Show all sections

Classification of AndalusiteHide

Approved, 'Grandfathered' (first described prior to 1959)
9.AF.10

9 : SILICATES (Germanates)
A : Nesosilicates
F : Nesosilicates with additional anions; cations in [4], [5] and/or only [6] coordination
52.2.2b.1

52 : NESOSILICATES Insular SiO4 Groups and O,OH,F,H2O
2 : Insular SiO4 Groups and O, OH, F, and H2O with cations in [4] and >[4] coordination
15.1

15 : Silicates of Aluminum

Physical Properties of AndalusiteHide

Vitreous, Sub-Vitreous, Greasy
Transparency:
Transparent, Translucent
Colour:
Pink to red brown, occasionally yellow, green, white, gray rarely violet
Comment:
in thin section, colorless to pink or green.
Streak:
White
Hardness:
6½ - 7½ on Mohs scale
Tenacity:
Brittle
Cleavage:
Distinct/Good
Good on {110}
Poor on {100}
Fracture:
Irregular/Uneven, Sub-Conchoidal
Density:
3.13 - 3.21 g/cm3 (Measured)    3.149 g/cm3 (Calculated)

Optical Data of AndalusiteHide

Type:
Biaxial (-)
RI values:
nα = 1.629 - 1.640 nβ = 1.633 - 1.644 nγ = 1.638 - 1.650
2V:
Measured: 73° to 86°, Calculated: 80° to 84°
Birefringence:
0.009
Max Birefringence:
δ = 0.009 - 0.010
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
Surface Relief:
Moderate
Dispersion:
r < v strong
Pleochroism:
Weak
Comments:
X= reddish pink
Y=Z= greenish yellow
Clear colored crystals can show strong pleochroism (Faye and Harris, 1969)
Comments:
Iron substitution may dramatically increase RI and birefringence.

Chemical Properties of AndalusiteHide

Formula:
Al2(SiO4)O
IMA Formula:
Al2SiO5

Crystallography of AndalusiteHide

Crystal System:
Orthorhombic
Class (H-M):
mmm (2/m 2/m 2/m) - Dipyramidal
Space Group:
Pnnm
Setting:
Pnnm
Cell Parameters:
a = 7.798(7) Å, b = 7.9031(10) Å, c = 5.5566(5) Å
Ratio:
a:b:c = 0.987 : 1 : 0.703
Unit Cell V:
342.44 ų (Calculated from Unit Cell)
Z:
4
Morphology:
As euhedral crystals or columnar aggregates having nearly square cross sections, commonly elongated parallel to [001], to 20 cm. Crystals may be much interrupted due to intersection with outer minerals. Also fibrous, compact, massive.
Twinning:
On {101} - rare

Crystallographic forms of AndalusiteHide

Crystal Atlas:
Image Loading
Click on an icon to view
Andalusite no.1 - Goldschmidt (1913-1926)
Andalusite no.10 - Goldschmidt (1913-1926)
Andalusite no.14 - Goldschmidt (1913-1926)
Andalusite no.18 - Goldschmidt (1913-1926)
3d models and HTML5 code kindly provided by www.smorf.nl.

Toggle
Edge Lines | Miller Indicies | Axes

Transparency
Opaque | Translucent | Transparent

View
Along a-axis | Along b-axis | Along c-axis | Start rotation | Stop rotation

X-Ray Powder DiffractionHide

Image Loading

Radiation - Copper Kα
Data Set:
Data courtesy of RRUFF project at University of Arizona, used with permission.
Powder Diffraction Data:
d-spacingIntensity
5.55 (100)
4.53 (80)
3.93 (30)
3.53 (30)
2.77 (70)
2.27 (30)
2.18 (30)
2.17 (40)
Comments:
ICDD 39-376

Type Occurrence of AndalusiteHide

Geological Setting of Type Material:
Low pressure and low-temperature metamorphic rocks.

Synonyms of AndalusiteHide

Other Language Names for AndalusiteHide

Bosnian (Latin Script):Andaluzit
Croatian:Andaluzit
Esperanto:Andaluzito
Estonian:Andalusiit
Galician:Andalucita
Hungarian:Andalúzit
Italian:Andalusite
Japanese:紅柱石
Lithuanian:Andalūzitas
Polish:Andaluzyt
Portuguese:Andaluzita
Romanian:Andaluzit
Serbian (Cyrillic Script):Андалузит
Simplified Chinese:红柱石
Swedish:Andalusit

Varieties of AndalusiteHide

ChiastoliteCrystals of Andalusite containg cross-shaped inclusions of carbon. Common in some metamorphic rocks.
Titanian AndalusiteA titanium-bearing andalusite.
ViridineA manganese-bearing, green Andalusite.

Relationship of Andalusite to other SpeciesHide

Common AssociatesHide

BiotiteA series or subgroup of the Mica Group.
Cordierite(Mg,Fe)2Al3(AlSi5O18)
CorundumAl2O3
CorundumAl2O3
KyaniteAl2(SiO4)O
MuscoviteKAl2(AlSi3O10)(OH)2
SillimaniteAl2(SiO4)O
TourmalineA(D3)G6(T6O18)(BO3)3X3Z
Associated Minerals Based on Photo Data:
Quartz22 photos of Andalusite associated with Quartz on mindat.org.
Muscovite21 photos of Andalusite associated with Muscovite on mindat.org.
Diaspore14 photos of Andalusite associated with Diaspore on mindat.org.
Chlorite Group10 photos of Andalusite associated with Chlorite Group on mindat.org.
Milky Quartz7 photos of Andalusite associated with Milky Quartz on mindat.org.
Sillimanite6 photos of Andalusite associated with Sillimanite on mindat.org.
Albite-Anorthite Series6 photos of Andalusite associated with Albite-Anorthite Series on mindat.org.
Biotite5 photos of Andalusite associated with Biotite on mindat.org.
Kyanite4 photos of Andalusite associated with Kyanite on mindat.org.
Sericite3 photos of Andalusite associated with Sericite on mindat.org.

Related Minerals - Nickel-Strunz GroupingHide

9.AF.05SillimaniteAl2(SiO4)OOrth. mmm (2/m 2/m 2/m)
9.AF.10KanonaiteMn3+Al(SiO4)OOrth. mmm (2/m 2/m 2/m) : Pnnm
9.AF.15KyaniteAl2(SiO4)OTric. 1 : P1
9.AF.20MulliteAl4+2xSi2-2xO10-xOrth. mmm (2/m 2/m 2/m) : Pbam
9.AF.20Krieselite(Al,Ga)2(GeO4)(OH)2Orth. mmm (2/m 2/m 2/m) : Pnma
9.AF.23BoromulliteAl9BSi2O19Orth. mm2 : Cmc21
9.AF.25YoderiteMg(Al,Fe3+)3(SiO4)2O(OH)Mon. 2/m : P21/m
9.AF.30MagnesiostauroliteMg(Mg,Li)3(Al,Mg)18Si8O44(OH)4Mon. 2/m : B2/m
9.AF.30StauroliteFe2+2Al9Si4O23(OH)Mon. 2/m : B2/m
9.AF.30ZincostauroliteZn2Al9Si4O23(OH)Mon. 2/m : B2/m
9.AF.35TopazAl2(SiO4)(F,OH)2Orth. mmm (2/m 2/m 2/m)
9.AF.40NorbergiteMg3(SiO4)(F,OH)2Orth. mmm (2/m 2/m 2/m)
9.AF.45AlleghanyiteMn2+5(SiO4)2(OH)2Mon. 2/m : P21/b
9.AF.45Chondrodite(Mg,Fe2+)5(SiO4)2(F,OH)2Mon. 2/m : P21/b
9.AF.45ReinhardbraunsiteCa5(SiO4)2(OH,F)2Mon. 2/m : P21/b
9.AF.45KumtyubeiteCa5(SiO4)2F2Mon. 2/m : P21/b
9.AF.45HydroxylchondroditeMg5(SiO4)2(OH)2Mon. 2/m : P21/b
9.AF.50Humite(Mg,Fe2+)7(SiO4)3(F,OH)2Orth. mmm (2/m 2/m 2/m)
9.AF.50Manganhumite(Mn2+,Mg)7(SiO4)3(OH)2Orth.
9.AF.50Unnamed (Ca-analogue of Humite)Ca7(SiO4)4F2Orth. mmm (2/m 2/m 2/m)
9.AF.55ClinohumiteMg9(SiO4)4F2Mon. 2/m : P21/b
9.AF.55SonoliteMn2+9(SiO4)4(OH)2Mon.
9.AF.55HydroxylclinohumiteMg9(SiO4)4(OH)2Mon. 2/m
9.AF.60LeucophoeniciteMn2+7(SiO4)3(OH)2Mon. 2/m : P21/b
9.AF.65Ribbeite(Mn2+,Mg)5(SiO4)2(OH)2Orth.
9.AF.70JerrygibbsiteMn2+9(SiO4)4(OH)2Orth. mmm (2/m 2/m 2/m) : Pbcn
9.AF.75FranciscaniteMn2+6(V5+,☐)2(SiO4)2(O,OH)6Hex.
9.AF.75ÖrebroiteMn2+3(Sb5+,Fe3+)(SiO4)(O,OH)3Hex.
9.AF.75WeliniteMn2+6(W6+,Mg)2(SiO4)2(O,OH)6Trig. 3 : P3
9.AF.80EllenbergeriteMg6(Mg,Ti,Zr,◻)2(Al,Mg)6Si8O28(OH)10Hex.
9.AF.85Chloritoid(Fe2+,Mg,Mn2+)Al2(SiO4)O(OH)2Mon. 2/m : B2/b
9.AF.85MagnesiochloritoidMgAl2(SiO4)O(OH)2Mon. 2/m : B2/b
9.AF.85Ottrélite(Mn2+,Fe2+,Mg)Al2(SiO4)O(OH)2Mon.
9.AF.90PoldervaartiteCaCa[SiO3(OH)](OH)Orth. mmm (2/m 2/m 2/m) : Pbca
9.AF.90OlmiiteCaMn2+[SiO3(OH)](OH)Orth. mmm (2/m 2/m 2/m) : Pbca

Related Minerals - Dana Grouping (8th Ed.)Hide

52.2.2b.2KanonaiteMn3+Al(SiO4)OOrth. mmm (2/m 2/m 2/m) : Pnnm
52.2.2b.3YoderiteMg(Al,Fe3+)3(SiO4)2O(OH)Mon. 2/m : P21/m

Related Minerals - Hey's Chemical Index of Minerals GroupingHide

15.2KyaniteAl2(SiO4)OTric. 1 : P1
15.3SillimaniteAl2(SiO4)OOrth. mmm (2/m 2/m 2/m)
15.4MulliteAl4+2xSi2-2xO10-xOrth. mmm (2/m 2/m 2/m) : Pbam
15.5PyrophylliteAl2Si4O10(OH)2Tric. 1
15.6DickiteAl2(Si2O5)(OH)4Mon. m : Bb
15.7NacriteAl2(Si2O5)(OH)4Mon. m : Bb
15.8KaoliniteAl2(Si2O5)(OH)4Tric. 1 : P1
15.9MetahalloysiteAl2(Si2O5)(OH)4
15.10HalloysiteAl2(Si2O5)(OH)4Mon. m : Bb
15.11Allophane(Al2O3)(SiO2)1.3-2 · 2.5-3H2OAmor.

Fluorescence of AndalusiteHide

Not fluorescent.

Other InformationHide

Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Andalusite in petrologyHide

References for AndalusiteHide

Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Delamétherie, J.C. (1798) Sur une pierre de l´andalousie. Journal de Physique, de Chimie et d´Histoire Naturelle: 46: 386-387.
Peck, A.B. (1924) Note on andalusite from California; a new use and some thermal properties. American Mineralogist: 9: 123-129.
Pearson, G.R., Shaw, D.M. (1960) Trace elements in kyanite, sillimanite and andalusite. American Mineralogist: 45: 808-817.
Burnham, C.W., Buerger, M.J. (1961) Refinement of the crystal structure of andalusite. Zeitschrift für Kristallographie: 115: 269-290.
Sgarlata F. (1962) Sulla struttura cristallina dell'andalusite. Periodico di Mineralogia: 43-61.
Chinner, G.A., Smith, J.W., Knowles, C.R. (1969) Transition metal contents of Al2SiO5 polymorphs. American Journal of Science: 267A: 96-113.
Faye, G.H., Harris, D.C. (1969) On the origin of colour and pleochroism in andalusite from Brazil. The Canadian Mineralogist: 10: 47-56.
Hafner, S.S., Raymond, M., Ghose, S. (1970) Nuclear quadrupole coupling tensors of Al27 in andalusite (Al2SiO5). Journal of Chemical Physics: 52: 6037-6041.
Finger, L.W., Prince, E. (1972) Neutron diffraction studies: andalusite and sillimanite. Carnegie Institution of Washington, Year Book: 71: 496-500.
Vaughan, M.T., Weidner, D.J. (1978) The relationship of elasticity and crystal structure in andalusite and sillimanite. Physics and Chemistry of Minerals: 3: 133-144.
Winter, J.K., Ghose, S. (1979) Thermal expansion and high-temperature crystal chemistry of the Al2SiO5 polymorphs. American Mineralogist: 64: 573-586.
Ralph, R.L., Finger, L.W., Hazen, R.M., Ghose, S. (1984) Compressibility and crystal structure of andalusite at high pressure. American Mineralogist: 69: 513-519.
Vernon, R.H., Flood, R.H., D'Arcy, W.F. (1987) Sillimanite and andalusite produced by base-cation leaching and contact metamorphism of felsic igneous rocks. Journal of Metamorphic Geology: 5: 439-450.
Kerrick, D.M. (1990) Metamorphic reactions. In D.M. Kerrick, Ed., The Al2SiO5 polymorphs. 22, 223-253. Reviews in Mineralogy. Mineralogical Society of America, Chantilly, Virginia.
Kerrick, D.M. (1990) The Al2SiO5 polymorphs, 22, 406 p. Reviews in Mineralogy, Mineralogical Society of America, Chantilly, Virginia.
Bryant, P.L., Harwell, C.R., Wu, K., Fronczek, F.R., Hall, R.W., Butler, L.G. (1999) Single-crystal 27 Al NMR of andalusite and calculated electric field gradients: the first complete NMR assignment for a 5-coordinated aluminum site. Journal of Physical Chemistry A, 103: 5246-5252.
Dahaoui, S., Ghermani, N.E., Ghose, S., Howard, J.A.K. (2001) Electric field gradient tensors at the aluminum sites in the Al2SiO5 polymorphs from CCD high-resolution X-ray diffraction data: comparison with 27 Al NMR results. American Mineralogist: 86: 159-164.
Iglesias, M., Schwarz, K., Blaha, P., Baldomir, D. (2001) Electronic structure and electric field gradient calculations of Al2SiO5 polymorphs. Physics and Chemistry of Minerals: 28: 67-75.
Winkler, B., Hytha, M., Warren, M.C., Milman, V., Gale, J.D., Schreuer, J. (2001) Calculation of the elastic constants of the Al2SiO5 polymorphs andalusite, sillimanite, and kyanite. Zeitschrift für Kristallographie: 216: 67-70.
Burt, J.B., Ross, N.L., Angel, R.J., Koch, M. (2006) Equations of state and structures of andalusite to 9.8 GPa and sillimanite to 8.5 GPa. American Mineralogist: 91: 319-326.
Ohuchi, F.S., Ghose, S., Engelhard, M.H., Baer, D.R. (2006) Chemical bonding and electronic structures of the Al2SiO5 polymorphs, andalusite, sillimanite, and kyanite: X-ray photoelectron- and electron energy loss spectroscopy studies. American Mineralogist: 91: 740-746.
Calvo Rebollar, M. (2016) El "lapis crucifer", "piedra de cruz de Compostela": un elemento importante de los patrimonios geológico y cultural del NW de España. De Re Metallica, 26, 67-79.

Internet Links for AndalusiteHide

Localities for AndalusiteHide

This 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.

Locality ListShow

Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2017, except where stated. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: November 20, 2017 13:43:31
Go to top of page