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Siderite

A valid IMA mineral species - grandfathered
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About SideriteHide

Formula:
FeCO3
Colour:
Yellowish-brown to greyish-brown, pale yellow to tannish, grey, brown, green, red, black and, rarely, colourless; tarnished iridescent at times; colourless to yellow and yellow-brown in transmitted light.
Lustre:
Vitreous, Silky, Pearly
Hardness:
3½ - 4½
Specific Gravity:
3.96
Crystal System:
Trigonal
Member of:
Name:
Named in 1845 by Wilhelm Karl von Haidinger from the Greek "σίδηρος" (sideros), "iron", in allusion to its composition.
Calcite Group. Magnesite-Siderite Series, Rhodochrosite-Siderite Series, Siderite-Smithsonite Series.

Crystals typically found as brown to tan rhombohedrons in clusters, faces often curved or composites; more often found as medium to dark brown massive fine-grained material or as massive crystalline material with exposed curved cleavage surfaces.

Fungi like Lichenothelia may oxidize iron to produce siderite, which is then a biomineral (e.g., Burford et al., 2003).




Unique IdentifiersHide

Mindat ID:
3647
Long-form identifier:
mindat:1:1:3647:0
GUID
(UUID V4):
ea4ee0ae-95d0-4330-a83e-558d6d01833f

IMA Classification of SideriteHide

Approved, 'Grandfathered' (first described prior to 1959)
IMA Formula:
Fe(CO3)

Classification of SideriteHide

5.AB.05

5 : CARBONATES (NITRATES)
A : Carbonates without additional anions, without H2O
B : Alkali-earth (and other M2+) carbonates
Dana 7th ed.:
14.1.1.3
14.1.1.3

14 : ANHYDROUS NORMAL CARBONATES
1 : A(XO3)
11.13.1

11 : Carbonates
13 : Carbonates of Fe

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
SdIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
SdKretz (1983)Kretz, R. (1983) Symbols of rock-forming minerals. American Mineralogist, 68, 277–279.
SdSiivolam & 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
SdWhitney & 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
SdThe Canadian Mineralogist (2019)The Canadian Mineralogist (2019) The Canadian Mineralogist list of symbols for rock- and ore-forming minerals (December 30, 2019). download
SdWarr (2020)Warr, L.N. (2020) Recommended abbreviations for the names of clay minerals and associated phases. Clay Minerals, 55, 261–264 doi:10.1180/clm.2020.30

Pronunciation of SideriteHide

Pronunciation:
PlayRecorded byCountry
Jolyon RalphUnited Kingdom

Physical Properties of SideriteHide

Vitreous, Silky, Pearly
Transparency:
Translucent
Colour:
Yellowish-brown to greyish-brown, pale yellow to tannish, grey, brown, green, red, black and, rarely, colourless; tarnished iridescent at times; colourless to yellow and yellow-brown in transmitted light.
Streak:
White
Hardness:
3½ - 4½ on Mohs scale
Hardness Data:
Measured
Tenacity:
Brittle
Cleavage:
Perfect
Perfect on {1011}.
Fracture:
Irregular/Uneven, Conchoidal
Density:
3.96(1) g/cm3 (Measured)    3.932 g/cm3 (Calculated)

Optical Data of SideriteHide

Type:
Uniaxial (-)
RI values:
nω = 1.875 nε = 1.633
Max Birefringence:
δ = 0.242
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
Surface Relief:
High
Dispersion:
Strong

Chemistry of SideriteHide

Mindat Formula:
FeCO3
Common Impurities:
Mn,Mg,Ca,Zn,Co

Crystallography of SideriteHide

Crystal System:
Trigonal
Class (H-M):
3m (3 2/m) - Hexagonal Scalenohedral
Space Group:
R3c
Cell Parameters:
a = 4.6916 Å, c = 15.3796 Å
Ratio:
a:c = 1 : 3.278
Unit Cell V:
293.17 ų (Calculated from Unit Cell)
Z:
6
Morphology:
Crystals usually rhombohedral {1011} or {0112}, often curved or with composite faces; also more rarely thin to thick tabular {0001}, prismatic [0001] with {1120}, or scalenohedral; most often found as massive material, either fine-grained in sedimentary settings or massively crystalline in metamorphic settings; may also be botryoidal or globular with a fibrous internal structure.
Twinning:
On {0112}, lamellar, uncommon, with translation gliding on {0001} or {1011}. On {0001}, rare.

Crystallographic forms of SideriteHide

Crystal Atlas:
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Siderite no.27 - Goldschmidt (1913-1926)
Siderite no.50 - Goldschmidt (1913-1926)
3d models and HTML5 code kindly provided by www.smorf.nl.

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0000101SideriteGraf D L (1961) Crystallographic tables for the rhombohedral carbonates American Mineralogist 46 1283-131619610293
0020837SideriteEffenberger H, Mereiter K, Zemann J (1981) Crystal structure refinements of magnesite, calcite, rhodochrosite, siderite, smithsonite, and dolomite, with discussion of some aspects of the stereochemistry of calcite type carbonates Zeitschrift fur Kristallographie 156 233-2431981Ivigtut, Greenland0293
0017561SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland0.02293
0017562SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland1.89293
0017563SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland3.48293
0017564SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland4.89293
0017565SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland7.31293
0017566SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland14.4293
0017567SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland18.37293
0017568SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland18.82293
0017569SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland19.19293
0017570SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland28.62293
0017571SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland30.6293
0017572SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland36.3293
0017573SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland38.5293
0017574SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland39.05293
0017575SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland39293
0017576SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland41.2293
0017577SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland43.9293
0017578SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland44.14293
0017579SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland45.13293
0017580SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland46.4293
0017581SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland46.92293
0017582SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland47.2293
0017583SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland47.49293
0017584SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland49.2293
0017585SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland51.9293
0017586SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland52.6293
0017587SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland54293
0017588SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland55.96293
0017589SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland55293
0017590SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland55293
0017591SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland55293
0017592SideriteLavina B, Dera P, Downs R T, Yang W, Sinogeikin S, Meng Y, Shen G, Schiferl D (2010) Structure of siderite FeCO3 to 56 GPa and hysteresis of its spin-pairing transition Physical Review B82 064110-82010Invigtut, Greenland55293
CIF Raw Data - click here to close

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
3.59 Å(30)
2.80 Å(100)
2.35 Å(20)
2.13 Å(20)
1.965 Å(20)
1.738 Å(30)
1.732 Å(40)
1.506 Å(10)

Geological EnvironmentHide

Paragenetic Mode(s):
Geological Setting:
Most often found in bedded sedimentary deposits with a biological component, with shales, clays and coal beds - suggesting that the siderite is biogenically created under low-oxygen and low-Ph conditions. It is also found in metamorphosed sedimentary rocks as more massively crystalline material, as a primary gangue mineral in hydrothermal deposits, and in pegmatites, including nepheline syenite pegmatites; as bog deposits.

Synonyms of SideriteHide

Other Language Names for SideriteHide

Varieties of SideriteHide

Ca-rich SideriteA calcian siderite, with up to 20 mol% of calcite.
Originally reported from Radstadt, Salzburg, Austria.
Kobalt-oligonspathA cobalt-bearing siderite.
Kolloid-sideriteA collodial variety of Siderite
Lady's SlipperAn epimorph of Siderite after Baryte collected in reasonable numbers in the 19th century from the Virtuous Lady mine in Devon and widely distributed in collections worldwide. How the Siderite managed to remain unaltered while the Baryte was subsequently d...
Manganese-bearing Siderite
Manganosphaerite
Mg-rich SideriteA Mg-rich variety of siderite.
If Mg>Fe, see Iron-bearing Magnesite.
OligoniteAn unnecessary name for a manganoan variety of siderite, with up to 40% MnCO3 [Clark, 1993 - "Hey's Mineral Index"].
PelosideriteA fine grained, concretionary variety of siderite.
PistomesiteObsolete name for a Mg-bearing variety of siderite with the Fe:Mg atomic ratio ranging from 70:30 to 50:50.

Originally reported from Thurnberg Mt., Flachau, Radstadt, Salzburg, Austria.
SideroplesiteObsolete name for a Mg-bearing variety of siderite with the Fe:Mg atomic ratio ranging from 70:30 to 90:10.
SphärosideriteA microcrystalline, botryoidal to spheroidal variety of siderite.
Occurs in voids in volcanic rocks or hydrothermal veins; also as concretions.
A low-temperature formation.
Wood iron (2)A fibrous variety of siderite

See also Wood Iron (1): fibrous goethite.
Zinc-bearing SideriteA zinc-bearing variety of siderite.

Relationship of Siderite to other SpeciesHide

Member of:
Other Members of this group:
CalciteCaCO3Trig. 3m (3 2/m) : R3c
GaspéiteNiCO3Trig. 3m (3 2/m) : R3c
MagnesiteMgCO3Trig. 3m (3 2/m) : R3c
OtaviteCdCO3Trig. 3m (3 2/m) : R3c
RhodochrositeMnCO3Trig. 3m (3 2/m) : R3c
SmithsoniteZnCO3Trig. 3m (3 2/m) : R3c
SpherocobaltiteCoCO3Trig. 3m (3 2/m) : R3c
Forms a series with:

Common AssociatesHide

Associated Minerals Based on Photo Data:
4,659 photos of Siderite associated with QuartzSiO2
2,304 photos of Siderite associated with CalciteCaCO3
2,115 photos of Siderite associated with PyriteFeS2
1,692 photos of Siderite associated with SphaleriteZnS
1,325 photos of Siderite associated with GalenaPbS
993 photos of Siderite associated with ChalcopyriteCuFeS2
858 photos of Siderite associated with FluoriteCaF2
828 photos of Siderite associated with FluorapatiteCa5(PO4)3F
584 photos of Siderite associated with DolomiteCaMg(CO3)2
546 photos of Siderite associated with BaryteBaSO4

Related Minerals - Strunz-mindat GroupingHide

5.AB.05CalciteCaCO3Trig. 3m (3 2/m) : R3c
5.AB.05GaspéiteNiCO3Trig. 3m (3 2/m) : R3c
5.AB.05MagnesiteMgCO3Trig. 3m (3 2/m) : R3c
5.AB.05OtaviteCdCO3Trig. 3m (3 2/m) : R3c
5.AB.05RhodochrositeMnCO3Trig. 3m (3 2/m) : R3c
5.AB.05SmithsoniteZnCO3Trig. 3m (3 2/m) : R3c
5.AB.05SpherocobaltiteCoCO3Trig. 3m (3 2/m) : R3c
5.AB.05 vaParakutnohorite
5.AB.10AnkeriteCa(Fe2+,Mg)(CO3)2Trig. 3 : R3
5.AB.10DolomiteCaMg(CO3)2Trig. 3 : R3
5.AB.10KutnohoriteCaMn2+(CO3)2Trig. 3 : R3
5.AB.10MinrecorditeCaZn(CO3)2Trig. 3 : R3
5.AB.10ŠkáchaiteCaCo(CO3)2Trig. 3 : R3
5.AB.15AragoniteCaCO3Orth. mmm (2/m 2/m 2/m)
5.AB.15CerussitePbCO3Orth. mmm (2/m 2/m 2/m)
5.AB.15StrontianiteSrCO3Orth. mmm (2/m 2/m 2/m)
5.AB.15WitheriteBaCO3Orth. mmm (2/m 2/m 2/m)
5.AB.20VateriteCaCO3Hex. 6/mmm (6/m 2/m 2/m) : P63/mmc
5.AB.25HuntiteCaMg3(CO3)4Trig. 3 2 : R3 2
5.AB.30NorsethiteBaMg(CO3)2Trig. 3 2 : R3 2
5.AB.35AlstoniteBaCa(CO3)2Tric.
5.AB.40OlekminskiteSr(Sr,Ca,Ba)(CO3)2Trig. 3 2 : P3 2 1
5.AB.40ParalstoniteBaCa(CO3)2Trig. 3 2 : P3 2 1
5.AB.45BarytocalciteBaCa(CO3)2Mon. 2/m : P21/m
5.AB.50Carbocernaite(Ca,Na)(Sr,Ce,Ba)(CO3)2Orth. mm2
5.AB.55BenstoniteBa6Ca6Mg(CO3)13Trig. 3 : R3
5.AB.60JuangodoyiteNa2Cu(CO3)2Mon. 2/m : P21/b

Other InformationHide

Magnetism:
Paramagnetic
Notes:
Slighty soluble in water.
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:
An ore of iron when found in sufficient volumes to be economically recoverable.

Siderite in petrologyHide

Internet Links for SideriteHide

References for SideriteHide

Reference List:

Localities for SideriteHide

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

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