Haematite

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Haematite
Brazilian trigonal haematite crystal
General
CategoryOxide minerals
Formula
(repeatin unit)
airn(III) oxide, Fe2O3, α-Fe2O3
Strunz clessification04.CB.05
Creestal seestemTrigonal
Space groupTrigonal hexagonal scalenohedral
H-M symbol: (32/m)
Space group: R3c
Unit cella = 5.038(2) Å, c = 13.772(12) Å; Z = 6
Identification
ColourMetallic gray, dull tae bricht reid
Creestal habitTabular tae thick crystals; micaceous or platy, commonly in rosettes; radiatin fibrous, reniform, botryoidal or stalactitic masses, columnar; yirdy, granular, oolitic
TwinninPenetration an lamellar
CleavageNone, mey shaw pairtins on {0001} an {1011}
FracturUneven tae sub-conchoidal
TenacityBrickle
Mohs scale haurdness5.5–6.5
SkinkleMetallic tae splendent
StreakBricht reid tae mirk reid
DiaphaneityOpaque
Speceefic gravity5.26
Optical propertiesUniaxial (-)
Refractive indexnω = 3.150–3.220, nε = 2.870–2.940
Birefringenceδ = 0.280
PleochroismO = brounish reid; E = yellaeish reid
References[1][2][3]

Haematite, is the mineral form o airn(III) oxide (Fe2O3), ane o several airn oxides.

References[eedit | eedit soorce]

  1. Anthony, John W.; Bideaux, Richard A.; Bladh, Kenneth W. and Nichols, Monte C. (ed.). "Hematite". Handbook of Mineralogy (PDF). III (Halides, Hydroxides, Oxides). Chantilly, VA, US: Mineralogical Society of America. ISBN 0962209724. Retrieved 5 December 2011.CS1 maint: multiple names: eeditors leet (link)
  2. Hematite. Webmineral.com. Retrieved on 2011-06-22.
  3. Hematite. Mindat.org. Retrieved on 2011-06-22.