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Corundum

A valid IMA mineral species - grandfathered
This page kindly sponsored by Eric D. Fritzsch
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About CorundumHide

Formula:
Al2O3
As a Commodity:
Colour:
Colourless, blue, red, pink, yellow, grey, golden-brown
Lustre:
Adamantine, Vitreous, Pearly
Hardness:
9
Specific Gravity:
3.98 - 4.1
Crystal System:
Trigonal
Member of:
Name:
Named "corinvindum" in 1725 by John Woodward and derived from the Sanskrit, kuruvinda ("Ruby"). Richard Kirwan used the current spelling "corundum" in 1794. Known by many names in ancient times: adamant, sapphire, ruby, hyacinthos, asteria, etc.
The aluminum analogue of Eskolaite, Hematite, and Karelianite.
The red (Cr-bearing) gem variety is called Ruby.
The blue (Fe- and Ti-bearing) gem variety is called Sapphire.

Compare 'silicon spinel', that might be similar to the gamma form of Al2O3.

Paglia (2004) reports the following calcination pathway: gibbsite → böhmite → γ-Al2O3 (Unnamed (gamma-alumina)) → δ-Al2O3 (synthetic equivalent of deltalumite) → θ-Al2O3 (synthetic equivalent of UM1990-23-O:Al) → α-Al2O3 (corundum).




Unique IdentifiersHide

Mindat ID:
1136
Long-form identifier:
mindat:1:1:1136:1

IMA Classification of CorundumHide

Approved, 'Grandfathered' (first described prior to 1959)

Classification of CorundumHide

4.CB.05

4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodates)
C : Metal: Oxygen = 2: 3,3: 5, and similar
B : With medium-sized cations
Dana 7th ed.:
4.3.1.1
4.3.1.1

4 : SIMPLE OXIDES
3 : A2X3
7.6.1

7 : Oxides and Hydroxides
6 : Oxides of Al

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.

SymbolSourceReference for Standard
CrnIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
CrnKretz (1983)Kretz, R. (1983) Symbols of rock-forming minerals. American Mineralogist, 68, 277–279.
CrnSiivolam & Schmid (2007)Siivolam, J. and Schmid, R. (2007) Recommendations by the IUGS Subcommission on the Systematics of Metamorphic Rocks: List of mineral abbreviations. Web-version 01.02.07. IUGS Commission on the Systematics in Petrology. download
CrnWhitney & Evans (2010)Whitney, D.L. and Evans, B.W. (2010) Abbreviations for names of rock-forming minerals. American Mineralogist, 95, 185–187 doi:10.2138/am.2010.3371
CrnThe Canadian Mineralogist (2019)The Canadian Mineralogist (2019) The Canadian Mineralogist list of symbols for rock- and ore-forming minerals (December 30, 2019). download

Pronunciation of CorundumHide

Pronunciation:
PlayRecorded byCountry
Jolyon RalphUnited Kingdom

Physical Properties of CorundumHide

Adamantine, Vitreous, Pearly
Transparency:
Transparent, Translucent, Opaque
Colour:
Colourless, blue, red, pink, yellow, grey, golden-brown
Streak:
White
Hardness:
Hardness Data:
Mohs hardness reference species
Tenacity:
Brittle
Cleavage:
None Observed
Parting:
Rhombohedral and basal parting {0001}, sometimes perfect but interrupted; also on {1011} due to exsolution (Boehmite), observed on large blocks (Georgia, USA).
Fracture:
Irregular/Uneven, Conchoidal
Density:
3.98 - 4.1 g/cm3 (Measured)    3.997 g/cm3 (Calculated)

Optical Data of CorundumHide

Type:
Uniaxial (-)
RI values:
nω = 1.767 - 1.772 nε = 1.759 - 1.763
2V:
Measured: 58°
Birefringence:
Low, first-order greys and whites.
Max. Birefringence:
δ = 0.008 - 0.009
Based on recorded range of RI values above.

Interference Colours:
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.

Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.

Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.

Surface Relief:
Very High (positive)
Relative to Canada balsam mounting medium (n ≈ 1.537).

This shows the grain boundary and Becke line effect under plane-polarised light, based on the contrast between this mineral's average refractive index and the mounting medium. It does not take into account mineral colouration.
In focus
Interference Figure:
This shows the idealized uniaxial interference figure - the conoscopic (convergent-light, Bertrand-lens-in) view, for a grain cut with the optic axis centred and vertical. The coloured rings are isochromatics, computed with the same physics as the Michel-Lévy bar above; the dark cross is the isogyre.

For a genuinely uniaxial mineral viewed this way, that cross stays perfectly stationary if you rotate the stage - unlike a biaxial mineral, where it splits apart on rotation. That invariance is itself the standard diagnostic test for telling uniaxial and biaxial minerals apart at the microscope.
Colour in reflected light:
Colourless
Pleochroism:
Not Visible
Comments:
Weak in sapphire (e = blue-green to yellow-green, o = pale to deep blue), otherwise none visible.
Comments:
Asterism often present due to oriented needle-like inclusions or to colloidal or other material deposited in oriented tubules.

Chemistry of CorundumHide

Mindat Formula:
Al2O3
Element Weights:
Element% weight
Al52.925 %
O47.075 %

Calculated from ideal end-member formula.
Common Impurities:
Cr,Fe,V,Ti

Crystallography of CorundumHide

Crystal System:
Trigonal
Class (H-M):
3m(32/m) - Hexagonal Scalenohedral
Space Group:
R3c
Cell Parameters:
a = 4.75 Å, c = 12.982 Å
Ratio:
a:c = 1 : 2.733
Unit Cell V:
253.54 ų
Z:
6
Morphology:
Often steep pyramidal on w, z, E, or ω. Barrel-shaped crystals that are often rough and rounded, of considerable size at times, varying from short prismatic [0001] with a large base to steep pyramidal. Less commonly, flat tabular {0001} or rhombohedral. Striae on {0001} parallel [0110]. Lines in the direction [1120] divide the base into six sectors at times.

Forms include {0001}, {1000}, {1120}, {7180}, {1015}, {1013}, {1012}, {1011}, {7072}, {7071}, {0111}, {0221}, {0772}, {2245}, {2243}, {7·7·14·9}, {1121}, {7·7·14·6}, {4488}, {11·11·22·6}, {2241}, {7·7·14·3}, {8·8·16·3}, {4481}, {14·14·28·3}, {4265}, {3254}, {2·8·10·9}
Twinning:
1. Common {1011}; usually lamellar, producing a lamellar structure and striae on c and r. Less commonly penetration twins or arrowhead twins with crystals tabular {1120}. 2. On {0001}, less common. Pressure twinning produced on {1011}, and on {0001}.

Crystallographic forms of CorundumHide

Crystal Atlas:
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Corundum no.17 - {hhl} - Goldschmidt (1913-1926)
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Corundum no.34 - {773} - Goldschmidt (1913-1926)
3d models and HTML5 code kindly provided by www.smorf.nl.

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0009327CorundumKirfel A, Eichhorn K (1990) Accurate structure analysis with synchrotron radiation. The electron density in Al2O3 and Cu2O Acta Crystallographica A46 271-2841990synthetic0293
0010593CorundumNewnham R E, de Haan Y M (1962) Refinement of the alpha Al2O3, Ti2O3, V2O3 and Cr2O3 structures Zeitschrift fur Kristallographie 117 235-2371962synthetic0293
0014077CorundumPauling L, Hendricks S B (1925) Crystal structures of hematite and corundum Journal of the American Chemical Society 47 781-7901925Ceylon0293
0014072CorundumWang X, Hubbard C, Alexander K, Becher P (1994) Neutron diffraction measurements of the residual stresses in Al2O3 - ZrO2 (CeO2) ceramic composites _cod_database_code 1000059 Journal of the American Ceramic Society 77 1569-157519940293
0012859CorundumLutterotti L, Scardi P (1990) Simultaneous structure and size-strain refinement by the Rietveld method _cod_database_code 1000032 Journal of Applied Crystallography 23 246-25219900293
0015110CorundumTsirelson V, Antipin M, Gerr R, Ozerov R, Struchkov Y (1985) Ruby structure peculiarities derived from X-ray data. Localization of chromium atoms and electron deformation density _cod_database_code 1000017 Physica Status Solidi A87 425-43319850293
0009325CorundumLewis J, Schwarzenbach D, Flack H D (1982) Electric field gradients and charge density in corundum alpha-Al2O3 Acta Crystallographica A38 733-73919820293
0012921CorundumFinger L W, Hazen R M (1978) Crystal structure and compression of ruby to 46 kbar Journal of Applied Physics 49 5823-582619780.0001293
0012914Corundumd'Amour H, Schiferl D, Denner W, Schulz H, Holzapfel W B (1978) High-pressure single-crystal structure determinations for ruby up to 90 kbar using an automatic diffractometer Journal of Applied Physics 49 4411-441619780293
0010607CorundumSaalfeld H (1964) Strukturuntersuchungen im system Al2O3-Cr2O3 Zeitschrift fur Kristallographie 120 342-34819640293
0017671CorundumZachariasen W (1928) Untersuchungen ueber die Kristallstruktur von Sesquioxyden und Verbindungen ABO3 _cod_database_code 1010951 Skrifter utgitt av det Norske Videnskaps-Akademi i Oslo 1928 1-16519280293
0009699CorundumIshizawa N, Miyata T, Minato I, Marumo F, Iwai S (1980) A structural investigation of alpha-Al2O3 at 2170 K Acta Crystallographica B36 228-23019800300
0009700CorundumIshizawa N, Miyata T, Minato I, Marumo F, Iwai S (1980) A structural investigation of alpha-Al2O3 at 2170 K Acta Crystallographica B36 228-230198002170
0012922CorundumFinger L W, Hazen R M (1978) Crystal structure and compression of ruby to 46 kbar Journal of Applied Physics 49 5823-582619781.1293
0012923CorundumFinger L W, Hazen R M (1978) Crystal structure and compression of ruby to 46 kbar Journal of Applied Physics 49 5823-582619782.1293
0012924CorundumFinger L W, Hazen R M (1978) Crystal structure and compression of ruby to 46 kbar Journal of Applied Physics 49 5823-582619782.8293
0012915Corundumd'Amour H, Schiferl D, Denner W, Schulz H, Holzapfel W B (1978) High-pressure single-crystal structure determinations for ruby up to 90 kbar using an automatic diffractometer Journal of Applied Physics 49 4411-441619782.8293
0012925CorundumFinger L W, Hazen R M (1978) Crystal structure and compression of ruby to 46 kbar Journal of Applied Physics 49 5823-582619783.5293
0012916Corundumd'Amour H, Schiferl D, Denner W, Schulz H, Holzapfel W B (1978) High-pressure single-crystal structure determinations for ruby up to 90 kbar using an automatic diffractometer Journal of Applied Physics 49 4411-441619784.2293
0012926CorundumFinger L W, Hazen R M (1978) Crystal structure and compression of ruby to 46 kbar Journal of Applied Physics 49 5823-582619784.6293
0012917Corundumd'Amour H, Schiferl D, Denner W, Schulz H, Holzapfel W B (1978) High-pressure single-crystal structure determinations for ruby up to 90 kbar using an automatic diffractometer Journal of Applied Physics 49 4411-441619786293
0012918Corundumd'Amour H, Schiferl D, Denner W, Schulz H, Holzapfel W B (1978) High-pressure single-crystal structure determinations for ruby up to 90 kbar using an automatic diffractometer Journal of Applied Physics 49 4411-441619787.4293
0012927CorundumFinger L W, Hazen R M (1978) Crystal structure and compression of ruby to 46 kbar Journal of Applied Physics 49 5823-582619788293
0012919Corundumd'Amour H, Schiferl D, Denner W, Schulz H, Holzapfel W B (1978) High-pressure single-crystal structure determinations for ruby up to 90 kbar using an automatic diffractometer Journal of Applied Physics 49 4411-441619788.1293
0012920Corundumd'Amour H, Schiferl D, Denner W, Schulz H, Holzapfel W B (1978) High-pressure single-crystal structure determinations for ruby up to 90 kbar using an automatic diffractometer Journal of Applied Physics 49 4411-441619789293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Loading XRD data...
Data Set:
Data courtesy of RRUFF project at University of Arizona, used with permission.
Powder Diffraction Data:
d-spacingIntensity
3.48 Å(70)
2.551 Å(97)
2.379 Å(42)
2.085 Å(100)
1.7398 Å(42)
1.6014 Å(82)
1.3738 Å(45)

Geological EnvironmentHide

Paragenetic Mode(s):
Geological Setting:
Silica-poor rocks, such as Nepheline-Syenites, alkali igneous undersaturated rocks, contact aureoles in altered aluminous shales, aluminous xenoliths in high temperature plutonic and hypabyssal rocks, metamorphosed bauxite deposits, and as a detrital material in sediments.

Synonyms of CorundumHide

Other Language Names for CorundumHide

Varieties of CorundumHide

"Kashmir" Sapphire"Kashmir" sapphire is a trade term for the sapphire of violetish blue to pure blue hue with strong to vivid saturation and medium-dark tone. The stones have a velvety lustre due to minute inclusions. The colour is also known as "cornflower blue". "Kashmir...
Adamantine SparA silky brown variety of corundum.
AlundumAn artificial Corundum used as an abrasive.
Asteriated SapphireA variety of Sapphire exhibiting the property of asterism.
BarklyiteA magenta-coloured variety of ruby (corundum).
Originally reported from Victoria, Australia.
Blue AlexandriteA trade name for blue/violet sapphire.
Cat SapphireOriental sapphires of some value but not of the characteristic colour.
ChlorosaphirA deep green variety of Corundum from Drachenfels, Königswinter, Siebengebirge, North Rhine-Westphalia, Germany.
Chromium-bearing CorundumAn unnecessary name for a Cr-bearing corundum. Note that much corundum contains traces of Cr. Red, Cr-bearing corundum is ruby.
Ledo frozen fireA Fe Ti rich blue gem variety of Corundum
Oriental AmethystA purple gem variety of Corundum.
Oriental EmeraldA green gem variety of Corundum.
Oriental TopazA yellow gem variety of Corundum.
PadmaragayaA trade name for a yellow gem variety of Corundum.
PadparadschaA salmon-pink coloured gem sapphire.

It is GIA's opinion that this color range should be limited to light to medium tones of pinkish orange to orange-pink hues. Lacking delicacy, the dark brownish orange or even medium brownish orange tones of corundum f...
RubyA red, gem variety of corundum. The red colour is caused by minor amounts of trivalent Cr replacing Al in the crystal structure.

In traditional gemmological terms, ruby has to be blood-red and of clear, facetable quality to justify the name. However, in ...
SapphireMost commonly refers to a blue gem variety of corundum, but other coloured varieties of corundum are also described as sapphire, except red corundum, which is better known as ruby.

The dehydration of diaspore in corundum occurs between 525 and 550 °C, ...
Star CorundumA variety of corundum exhibiting a star pattern when viewed down the C axis. The chatoyance is due to oriented microscopic inclusions.
Star RubyA variety of ruby exhibiting a star pattern when viewed down the c axis. The chatoyance is due to oriented microscopic inclusions (nanorods) of diaspore (Nadin, 2007).
Star SapphireA variety of sapphire that exhibits a star pattern when viewed down the c axis. The chatoyance is due to oriented microscopic inclusions (nanorods) of diaspore (Nadin, 2007).

The Star of India is the largest star sapphire in the world (563 carats or 113 ...
Titanium-bearing Corundum
Trapiche rubyVariety showing six-spoked growth features.
Compare trapiche emerald.

Relationship of Corundum to other SpeciesHide

Member of:
Other Members of Hematite Group:
EskolaiteCr2O3Trig. 3m(32/m) : R3c
HematiteFe2O3Trig. 3m(32/m) : R3c
KarelianiteV3+2O3Trig. 3m(32/m) : R3c
TistariteTi3+2O3Trig. 3m(32/m) : R3c

Common AssociatesHide

Associations Based on Photo Data:
303 photos of Corundum associated with SpinelMgAl2O4
215 photos of Corundum associated with Magnesiohögbomite subgroup
104 photos of Corundum associated with CalciteCaCO3
79 photos of Corundum associated with PhlogopiteKMg3(AlSi3O10)(OH)2
65 photos of Corundum associated with BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
39 photos of Corundum associated with RutileTiO2
36 photos of Corundum associated with KyaniteAl2(SiO4)O
36 photos of Corundum associated with 'Sapphire'Al2O3
27 photos of Corundum associated with 'Ruby'Al2O3
26 photos of Corundum associated with MuscoviteKAl2(AlSi3O10)(OH)2

Related Minerals - Strunz-mindat GroupingHide

4.CB.Magnesiohögbomite-6N12SMg5Al11TiO23(OH)Trig. 3m(32/m) : R3m
4.CB.KidoditeBaMg2Fe16O27Hex. 6/mmm(6/m2/m2/m) : P63/mmc
4.CB.Ferrohögbomite-2N2S[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2Hex. 6mm : P63mc
4.CB.Zhenruite(MoO3)2 · H2OMon. 2/m : P21/m
4.CB.FuyuaniteMg7Nb6O18(OH)8Trig. 3 : P3
4.CB.VirgilluethiteMoO3 · H2OMon. 2/m : P21/b
4.CB.Pengite(Pb8Sb3+3)Σ11Sb5+9O35Trig. 3m(32/m) : R3m
4.CB.05BrizziiteNaSb5+O3Trig. 3 : R3
4.CB.05TistariteTi3+2O3Trig. 3m(32/m) : R3c
4.CB.05HematiteFe2O3Trig. 3m(32/m) : R3c
4.CB.05EcandrewsiteZnTiO3Trig. 3 : R3
4.CB.05MelanostibiteMn2+2Fe3+Sb5+O6Trig. 3 : R3
4.CB.05'UM1998-11-O-AuHSb'Au+2Sb3+O2(OH)
4.CB.05KarelianiteV3+2O3Trig. 3m(32/m) : R3c
4.CB.05EskolaiteCr2O3Trig. 3m(32/m) : R3c
4.CB.05GeikieliteMgTiO3Trig. 3 : R3
4.CB.05AkimotoiteMgSiO3Trig. 3 : R3
4.CB.05'Unnamed (Fe-Cr Oxide)'FeCrO3Trig. 3 : R3
4.CB.05'Auroantimonate'AuSbO3
4.CB.05HemleyiteFe2+SiO3Trig. 3 : R3
4.CB.05IlmeniteFe2+TiO3Trig. 3 : R3
4.CB.05PyrophaniteMn2+TiO3Trig. 3 : R3
4.CB.10Bixbyite-(Fe)(Fe,Mn)2O3Iso.
4.CB.10Bixbyite-(Mn)Mn3+2O3Iso. m3(2/m3) : Ia3
4.CB.10AvicenniteTl3+2O3Iso. m3(2/m3) : Ia3
4.CB.15ArmalcoliteMgTi4+2O5Orth. mmm(2/m2/m2/m)
4.CB.15FerropseudobrookiteFe2+Ti4+2O5Orth. mmm(2/m2/m2/m) : Cmcm
4.CB.15GriffiniteAl2Ti4+O5Orth. mmm(2/m2/m2/m) : Cmcm
4.CB.15Pseudobrookite Group
4.CB.15SassiteTi3+2Ti4+O5Orth. mmm(2/m2/m2/m) : Cmcm
4.CB.15PseudobrookiteFe3+2Ti4+O5Orth. mmm(2/m2/m2/m) : Cmcm
4.CB.20Zincovelesite-6N6SZn3(Fe3+,Mn3+,Al,Ti)8O15(OH)Trig. 3m(32/m) : P3m1
4.CB.20Magnesiohögbomite-2N4S(Mg8.43Fe2+1.57)Σ=10Al22Ti4+2O46(OH)2Hex. 6mm : P63mc
4.CB.20Magnesiobeltrandoite-2N3S(Mg6Al2)(Al18Fe3+2)O38(OH)2 Trig. 3m : P3m1
4.CB.20Zincohögbomite-2N6S[(Zn,Mg)7(Al,Fe3+,Ti)16O31(OH)]2Hex. 6mm : P63mc
4.CB.20Magnesiohögbomite-6N6S[(Mg,Fe2+)3(Al,Ti,Fe3+)8O15(OH)]6Trig. 3m(32/m) : R3m
4.CB.20Magnesiohögbomite-2N3S[(Mg,Fe2+,Zn)4(Al,Ti,Fe3+)10O19(OH)]2Trig. 3m(32/m) : P31m
4.CB.20Magnesiohögbomite-2N2S[(Mg,Fe2+)3[Al7(Ti,Fe3+)]O15(OH)]2Hex. 6mm : P63mc
4.CB.20'Ferrohögbomite-6N12S'[(Fe2+,Mg,Zn)5(Al,Ti,Fe3+)12O23(OH)]6Trig. 3m(32/m) : R3m
4.CB.20Zincohögbomite-2N2S[(Zn,Al,Fe2+)3(Al,Fe3+,Ti)8O15(OH)]2Hex. 6mm : P63mc
4.CB.25KleberiteFeTi6O11(OH)5Mon. 2/m : P21/b
4.CB.25PseudorutileFe3+2Ti4+3O9Hex. 622 : P6322
4.CB.30OxyvaniteV3+2V4+O5Mon. 2/m : B2/b
4.CB.30BerdesinskiiteV3+2TiO5Mon.
4.CB.30KaitianiteTi3+2Ti4+O5Mon. 2/m : B2/b
4.CB.35MachiiteAl2Ti3O9Mon. 2/m : B2/b
4.CB.35Vestaite(Ti4+Fe2+)Ti4+3O9Mon. 2/m : B2/b
4.CB.35Olkhonskite(Cr,V)2Ti3O9Mon.
4.CB.35SchreyeriteV3+2Ti4+3O9Mon. 2/m : B2/b
4.CB.40Zincorinmanite-(Zn)Zn2Sb2(Fe3+4Zn2)O14(OH)2Hex. 6mm : P63mc
4.CB.40MajindeiteMg2Mo3O8Hex. 6mm : P63mc
4.CB.40AlmagreraiteCuZnMn4+3O8Orth. mm2 : Pmn21
4.CB.40KamiokiteFe2Mo3O8Hex. 6mm : P63mc
4.CB.40NolaniteV3+8Fe3+2O14(OH)2Hex. 6mm : P63mc
4.CB.40IseiteMn2Mo3O8Hex. 6mm : P63mc
4.CB.40RinmaniteZn2Sb2Mg2Fe4O14(OH)2Hex. 6 : P63
4.CB.45StibioclaudetiteAsSbO3Mon. 2/m : P21/m
4.CB.45ClaudetiteAs2O3Mon. 2/m
4.CB.50SenarmontiteSb2O3Iso. m3m(4/m32/m) : Fd3m
4.CB.50ArsenoliteAs2O3Iso. m3m(4/m32/m) : Fd3m
4.CB.55ValentiniteSb2O3Orth. mmm(2/m2/m2/m) : Pccn
4.CB.60BismiteBi2O3Mon. 2/m : P21/b
4.CB.65SphaerobismoiteBi2O3Tet.
4.CB.70SilléniteBi12SiO20Iso. 23 : I23
4.CB.75KyzylkumiteV3+Ti2O5(OH)Mon. 2/m : P21/b
4.CB.80'Tietaiyangite'Fe3+4Fe2+TiO9Hex.
4.CB.85LiuiteFeTiO3Orth. mmm(2/m2/m2/m) : Pnma
4.CB.90LuogufengiteFe2O3Orth. mm2 : Pna21
4.CB.95WangdaodeiteFeTiO3Trig. 3m : R3c

Other InformationHide

Thermal Behaviour:
Before the blowpipe, unaltered.
Notes:
Not affected by acids.
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Industrial Uses:
Corundum is used as an abrasive ("Emery"), and the gem varieties of corundum are better-known as Ruby and Sapphire.

Corundum in petrologyHide

Internet Links for CorundumHide

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