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Coalingite

A valid IMA mineral species
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About CoalingiteHide

09302760017271922267220.jpg
Coalinga, California, USA
Formula:
Mg10Fe3+2(OH)24[CO3] · 2H2O
Colour:
Deep reddish brown, brown, straw-yellow; golden brown in transmitted light.
Lustre:
Resinous
Hardness:
1 - 2
Specific Gravity:
2.32 - 2.42
Crystal System:
Trigonal
Name:
Named for the town of Coalinga, California, USA, near the type locality. The name is pronounced kōl-inǵ-gīt.
This page provides mineralogical data about Coalingite.


Unique IdentifiersHide

Mindat ID:
1095
Long-form identifier:
mindat:1:1:1095:1

IMA Classification of CoalingiteHide

Classification of CoalingiteHide

5.DA.55

5 : CARBONATES (NITRATES)
D : Carbonates with additional anions, with H2O
A : With medium-sized cations
16b.7.6.1

16b : HYDRATED CARBONATES CONTAINING HYDROXYL OR HALOGEN
7 : Miscellaneous
11.13.5

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 for Standard
ClgIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
ClgWarr (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

Physical Properties of CoalingiteHide

Resinous
Transparency:
Translucent
Colour:
Deep reddish brown, brown, straw-yellow; golden brown in transmitted light.
Hardness:
1 - 2 on Mohs scale
Cleavage:
Distinct/Good
{0001}, perfect; another at 45°
Density:
2.32 - 2.42 g/cm3 (Measured)    2.26 g/cm3 (Calculated)

Optical Data of CoalingiteHide

Type:
Uniaxial (-)
RI values:
nω = 1.588 - 1.635 nε = 1.56 - 1.59
Max. Birefringence:
δ = 0.028 - 0.045
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:
Moderate (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.
Pleochroism:
Visible
Comments:
0 = golden brown, dark brown; E = colorless.
Comments:
May be anomalously biaxial.

Chemistry of CoalingiteHide

Mindat Formula:
Mg10Fe3+2(OH)24[CO3] · 2H2O
Element Weights:
Element% weight
O54.017 %
Mg28.296 %
Fe13.003 %
H3.286 %
C1.398 %

Calculated from ideal end-member formula.
O
Mg
Fe
H
C

Crystallography of CoalingiteHide

Crystal System:
Trigonal
Class (H-M):
3m(32/m) - Hexagonal Scalenohedral
Space Group:
R3m
Setting:
R3m
Cell Parameters:
a = 3.12 Å, c = 37.4 Å
Ratio:
a:c = 1 : 11.987
Unit Cell V:
315.29 ų (Calculated from Unit Cell)
Morphology:
Hexagonal plates, equant grains.
Twinning:
reflection across {0001}, common
Comment:
Z = 0.5

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0014454CoalingitePastor-Rodriguez J, Taylor H F W (1971) Crystal structure of coalingite Mineralogical Magazine 38 286-2941971New Idria serpentinite, Coalinga, California, USA0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
2.34 Å(100)
4.20 Å(80)
6.05 Å(50)
1.558 Å(50)
13.4 Å(40 broad)
2.67 Å(30)
1.884 Å(30)
Comments:
Coalinga, California, USA. Data from Mumpton et al. (1965).

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 5: Initiation of plate tectonics<3.5-2.5
38 : Ophiolites
Stage 7: Great Oxidation Event<2.4
47a : [Near-surface hydration of prior minerals]
47c : [Carbonates, phosphates, borates, nitrates]
Stage 10a: Neoproterozoic oxygenation/terrestrial biosphere<0.6
50 : Coal and/or oil shale minerals<0.36
Stage 10b: Anthropogenic minerals<10 Ka
54 : Coal and other mine fire minerals (see also #51 and #56)
57 : Other minerals formed by human processes

Type Occurrence of CoalingiteHide

General Appearance of Type Material:
Soft, reddish-brown platelets, 0.1 to 0.2 mm in size.
Place of Conservation of Type Material:
National Museum of Natural History, Washington, D.C., USA, number 119335.
Geological Setting of Type Material:
Weathering of iron rich brucite.
Associated Minerals at Type Locality:

Synonyms of CoalingiteHide

Other Language Names for CoalingiteHide

German:Coalingit
Spanish:Coalingita

Relationship of Coalingite to other SpeciesHide

Other Members of Hydrotalcite Supergroup:
Akopovaite Al4Li2(OH)12(CO3)(H2O)3Mon. 2/m : B2/m
AmoraiteCa12Al6(OH)36(CO3)2(SO3) · 15H2O Tric. 1 : P1
BrugnatelliteMg6Fe3+(CO3)(OH)13 · 4H2OHex.
CarbocalumiteCa4Al2(OH)12(CO3) · 6H2OTrig. 3m(32/m) : R3c
Cualstibite GroupM2R(OH)6[Sb5+(OH)6], where M = Zn, Ni, Cu and R = Al or Fe3+
DritsiteLi2Al4(OH)12Cl2 · 3H2OHex. 6/mmm(6/m2/m2/m) : P63/mcm
Fougèrite Group
Glaucocerinite Group
Hydrocalumite Group
Hydrotalcite GroupM6R3+2(OH)16Z · 4H2O, where M=Mg, Fe, Ni, R3+ = Al, Cr, Co or Fe, and Z=CO3, Cl
Marioantofilliite[Cu4Al2(OH)12](CO3) · 3H2OMon. 2/m : B2/m
MuskoxiteMg7Fe4O13 · 10H2OTrig. 3m(32/m)
PoellmanniteCa6Al3(OH)18[Na(H2O)6](SO4)2 · 6H2OTrig. 3 : R3
Quintinite Group
RotemiteCa4Cr2(OH)12Cl2 · 4H2OTrig. 3m(32/m) : R3c
'UM1987-05-OH:AlCMg'Mg4Al2(OH)12(CO3,SO4) · 3H2O
Wermlandite GroupM7R3+2(OH)18[Ca(H2O)6][SO4]2 · 6H2O, where = Mg, Fe, Zn and R= Al or Fe
Woodwardite GroupMay be considered a subgroup of the Hydrotalcite Group.

Common AssociatesHide

Associations Based on Photo Data:
4 photos of Coalingite associated with Serpentine SubgroupD3[Si2O5](OH)4
4 photos of Coalingite associated with CalciteCaCO3
3 photos of Coalingite associated with AntigoriteMg3(Si2O5)(OH)4
2 photos of Coalingite associated with HydromagnesiteMg5(CO3)4(OH)2 · 4H2O
2 photos of Coalingite associated with TalcMg3Si4O10(OH)2
2 photos of Coalingite associated with MagnetiteFe2+Fe3+2O4
1 photo of Coalingite associated with MagnesiteMgCO3
1 photo of Coalingite associated with ChrysotileMg3(Si2O5)(OH)4

Related Minerals - Strunz-mindat GroupingHide

5.DA.AlexkhomyakoviteK6(Ca2Na)(CO3)5Cl · 6H2OHex. 6/mmm(6/m2/m2/m) : P63/mcm
5.DA.AmoraiteCa12Al6(OH)36(CO3)2(SO3) · 15H2O Tric. 1 : P1
5.DA.05DypingiteMg5(CO3)4(OH)2 · 5H2OMon. 2 : P21
5.DA.05'UM1986-10-CO:ClHMgMnZn (also called Mineral F, Dunn, 1995)'Mg5(Zn,Mn)3(CO3)2(OH,Cl)12 · H2O
5.DA.05'UM1987-01-CO:HMgS'Mg4(CO3)2(OH)4 · 6H2O ?Mon.
5.DA.05GiorgiositeMg5(CO3)4(OH)2 · 5-6H2O
5.DA.05HydromagnesiteMg5(CO3)4(OH)2 · 4H2OMon. 2/m : P21/b
5.DA.05WidgiemoolthaliteNi5(CO3)4(OH)2 · 5H2OMon. 2/m : P21/b
5.DA.10ArtiniteMg2(CO3)(OH)2 · 3H2OMon. 2/m : B2/m
5.DA.10ChlorartiniteMg2(CO3)(OH)Cl · 2H2OTrig. 3m : R3c
5.DA.10IndigiriteMg2Al2(CO3)4(OH)2 · 15H2O
5.DA.15ZaratiteNi3(CO3)(OH)4 · 4H2O ?Iso.
5.DA.15OtwayiteNi2(CO3)(OH)2 · H2OOrth.
5.DA.20KambaldaiteNaNi4(CO3)3(OH)3 · 3H2OHex. 6 : P63
5.DA.25CallaghaniteCu2Mg2(CO3)(OH)6 · 2H2OMon. 2/m : B2/b
5.DA.30Claraite(Cu,Zn)15(CO3)4(AsO4)2(SO4)(OH)14 · 7H2OTric. 1 : P1
5.DA.35HydroscarbroiteAl14(CO3)3(OH)36 · nH2OTric.
5.DA.35ScarbroiteAl5(CO3)(OH)13 · 5H2OTric.
5.DA.40KarchevskyiteMg18Al9(OH)54Sr2(CO3)9(H2O)6(H3O)5Trig.
5.DA.40'UM1987-05-OH:AlCMg'Mg4Al2(OH)12(CO3,SO4) · 3H2O
5.DA.40QuintiniteMg4Al2(OH)12(CO3) · 3H2OHex. 622 : P6322
5.DA.40CharmariteMn2+4Al2(OH)12[CO3] · 3H2OHex.
5.DA.40CaresiteFe2+4Al2(OH)12[CO3] · 3H2OTrig. 32 : P3112
5.DA.45'Hydrotalcite-2H'Mg6Al2(CO3)(OH)16 · 4H2OHex. 6/mmm(6/m2/m2/m) : P63/mmc
5.DA.45'Stichtite-2H'Mg6(Cr,Al)2(CO3)(OH)16 · 4H2OHex. 6/mmm(6/m2/m2/m) : P63/mmc
5.DA.45BrugnatelliteMg6Fe3+(CO3)(OH)13 · 4H2OHex.
5.DA.45ZaccagnaiteZn4Al2(OH)12[CO3] · 3H2OHex.
5.DA.45'Pyroaurite-2H'Mg6Fe3+2(OH)16(CO3) · 4H2OHex. 6/mmm(6/m2/m2/m) : P63/mmc
5.DA.45LiudongshengiteZn4Cr2(OH)12(CO3) · 3H2OTrig. 3m(32/m) : R3m
5.DA.45ChlormagaluminiteMg4Al2(OH)12Cl2 · 3H2OHex. 6/mmm(6/m2/m2/m) : P63/mcm
5.DA.50PyroauriteMg6Fe3+2(OH)16[CO3] · 4H2OTrig. 3m(32/m) : R3m
5.DA.50TakoviteNi6Al2(OH)16[CO3] · 4H2OTrig. 3m(32/m) : R3m
5.DA.50ReevesiteNi6Fe3+2(OH)16(CO3) · 4H2OTrig. 3m(32/m) : R3m
5.DA.50KaznakhtiteNi6Co3+2(CO3)(OH)16 · 4H2OTrig. 3 : R3
5.DA.50ComblainiteNi4Co2(OH)12[CO3] · 3H2OTrig.
5.DA.50Marioantofilliite[Cu4Al2(OH)12](CO3) · 3H2OMon. 2/m : B2/m
5.DA.50HydrotalciteMg6Al2(CO3)(OH)16 · 4H2OTrig. 3m(32/m) : R3m
5.DA.50StichtiteMg6Cr3+2(OH)16[CO3] · 4H2OTrig. 3m(32/m) : R3m
5.DA.50DesautelsiteMg6Mn3+2(OH)16[CO3] · 4H2OTrig. 3m(32/m)
5.DA.55Akopovaite Al4Li2(OH)12(CO3)(H2O)3Mon. 2/m : B2/m
5.DA.60ŠlikiteZn2Mg(CO3)2(OH)2 · 4H2OTric. 1 : P1
5.DA.65MarkliteCu5(CO3)2(OH)6 · 6H2OMon. 2/m : P21/b

Other InformationHide

Thermal Behaviour:
DTA shows endothermic peaks at 175°, 310°, and 400° C.
Notes:
Iron-rich brucite specimens transformed to coalingite in the laboratory, exposed to the atmosphere for several months.
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Internet Links for CoalingiteHide

References for CoalingiteHide

Reference List:

Localities for CoalingiteHide

Showing 34 localities.

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.
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Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. - Good crystals or important locality for species. - World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.
Australia
 
  • New South Wales
    • Darling Co.
Oskierski et al. (2013) +1 other reference
  • Tasmania
    • Waratah-Wynyard municipality
R Bottrill
Austria
 
  • Styria
    • Bruck-Mürzzuschlag District
      • Breitenau am Hochlantsch
        • Eibegggraben
Bojar et al. (2005)
    • Murtal District
      • Sankt Margarethen bei Knittelfeld
        • Sankt Lorenzen bei Knittelfeld
Exel (1993)
Canada
 
  • Nunavut
    • Coppermine River area
Jambor (1969)
  • Québec
    • Abitibi-Témiscamingue
      • Abitibi RCM
        • Launay
Crook III et al. (1979)
    • Estrie
      • Les Sources RCM
        • Val-des-Sources
Horváth et al. (2013)
Czech Republic
 
  • South Moravian Region
    • Brno-Country District
      • Ivančice
        • Hrubšice
Kovář +1 other reference
Italy
 
  • Aosta Valley
    • Montjovet
Ferraris (1971) +2 other references
  • Liguria
    • Genoa
      • Cogoleto
Antofilli et al. (1985)
  • Lombardy
    • Sondrio Province
      • Lanzada
        • Franscia
Bedognè et al. (1993)
        • Scerscen Valley
Bedognè et al. (1993)
      • Torre di Santa Maria
        • Ciappanico
Bedognè et al. (1993)
Japan
 
  • Aichi Prefecture
    • Shinshiro city
Suzuki et al. (1976)
  • Fukuoka Prefecture
    • Kasuya District
上原誠一郎. (1987)
  • Hokkaidō Prefecture
    • Kamikawa Subprefecture
      • Nakagawa (Teshio) District
Yamada (2004)
  • Mie Prefecture
Färber (n.d.)
Yamada (2004)
Poland
 
  • Silesian Voivodeship
    • Wodzisław County
      • Wodzisław Śląski
Ł. Kruszewski (PXRD data)
Romania
 
  • Suceava County
    • Iacobeni
minerals-of-the-carpathians.eu (2008)
      • Tolovanu
Hîrtopanu (1997) +1 other reference
Russia
 
  • Chelyabinsk Oblast
Cesnokov et al. (1998)
  • Sakha
    • Khompu–May kimberlite field
Zayakina et al. (2015)
Spain
 
  • Andalusia
    • Málaga
      • Igualeja
González-Pérez et al. (2023)
USA (TL)
 
  • California
    • Fresno County
      • Wright Mountain
Mumpton et al. (1965) +2 other references
    • San Benito County
      • Idria (New Idria)
Pemberton (1983) +1 other reference
      • Idria Peak
www.mineralsocal.org (1999)
Mumpton et al. (1965)
      • Santa Rita Peak
Emil Box
    • San Francisco County
      • San Francisco
Learned (1965) +3 other references
  • Maryland
    • Montgomery County
      • Rockville
Bernstein (1980)
  • New York
    • New York City
Jensen (1978)
  • Pennsylvania
    • Lancaster County
      • Fulton Township
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