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Maxwellite

A valid IMA mineral species
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About MaxwelliteHide

Formula:
NaFe3+(AsO4)F
Colour:
Red
Lustre:
Vitreous, Sub-Vitreous
Hardness:
5 - 5½
Specific Gravity:
3.90
Crystal System:
Monoclinic
Member of:
Name:
Named by Eugene E. Foord, Paul F. Hlava, Joan J. Fitzpatrick, Richard C. Erd, and R. W. Hinton in honor of Charles Henry Maxwell (9 July 1923 – 29 May 2000 Denver, Colorado), geologist and mineralogist with the U.S. Geological Survey, who studied the Taylor Creek district.
Isostructural with:

Unique IdentifiersHide

Mindat ID:
2605
Long-form identifier:
mindat:1:1:2605:1

IMA Classification of MaxwelliteHide

Approved
IMA Formula:
NaFe3+As5+O4F
Approval year:
1987
First published:
1991

Classification of MaxwelliteHide

8.BH.10

8 : PHOSPHATES, ARSENATES, VANADATES
B : Phosphates, etc., with additional anions, without H2O
H : With medium-sized and large cations, (OH,etc.):RO4 = 1:1
41.5.5.3

41 : ANHYDROUS PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
5 : (AB)2(XO4)Zq
22.1.21

22 : Phosphates, Arsenates or Vanadates with other Anions
1 : Phosphates, arsenates or vanadates with fluoride

Mineral SymbolsHide

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

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

Physical Properties of MaxwelliteHide

Vitreous, Sub-Vitreous
Transparency:
Translucent
Colour:
Red
Streak:
Pale red-orange to red-orange
Hardness:
5 - 5½ on Mohs scale
Tenacity:
Brittle
Cleavage:
Distinct/Good
{110}
Fracture:
Irregular/Uneven
Density:
3.90 g/cm3 (Measured)    3.95 g/cm3 (Calculated)

Optical Data of MaxwelliteHide

Type:
Biaxial (+)
RI values:
nα = 1.748 nβ = 1.772 nγ = 1.798
2V:
Measured: 86° to 89°, Calculated: 90°
Birefringence:
0.050
Max. Birefringence:
δ = 0.050
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
Dispersion:
r > v strong
Comments:
X=Y= medium yellow-orange; Z= dark orange-red.

Chemistry of MaxwelliteHide

Mindat Formula:
NaFe3+(AsO4)F
Element Weights:
Element% weight
As31.646 %
O27.032 %
Fe23.588 %
Na9.711 %
F8.025 %

Calculated from ideal end-member formula.

Crystallography of MaxwelliteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P2/m
Cell Parameters:
a = 7.16 Å, b = 8.78 Å, c = 6.68 Å
β = 114.58°
Ratio:
a:b:c = 0.815 : 1 : 0.761
Unit Cell V:
381.88 ų (Calculated from Unit Cell)
Z:
4
Morphology:
Slightly elongated to blocky crystals.

Forms on type material: {013}, {526}, {526}, {011}.

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0014873MaxwelliteCooper M A, Hawthorne F C (1995) The crystal structure of maxwellite Neues Jahrbuch fur Mineralogie, Monatshefte 1995 97-1041995Squaw Creek, Catron County, New Mexico, USA0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
3.290 Å(100)
2.614 Å(80)
3.039 Å(75)
4.844 Å(70)
2.637 Å(50)
3.642 Å(35)
3.437 Å(35)
Comments:
Original description

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 4a: Earth’s earliest continental crust>4.4-3.0
20 : Acidic volcanic rocks
Stage 7: Great Oxidation Event<2.4
45a : [Sulfates, arsenates, selenates, antimonates]
45b : [Other oxidized fumarolic minerals]

Type Occurrence of MaxwelliteHide

General Appearance of Type Material:
Red aggregates to 3 mm and as blocky to short prismatic euhedral to subhedral crystals up to 1 mm long.
Place of Conservation of Type Material:
National Museum of Natural History, Washington, D.C., USA, 166613.
Geological Setting of Type Material:
Formed as a rarity in miarolitic cavities in rhyolite adjacent to high-temperature veins in a hydrothermal tin deposit.
Associated Minerals at Type Locality:

Synonyms of MaxwelliteHide

Other Language Names for MaxwelliteHide

Relationship of Maxwellite to other SpeciesHide

Member of:
Other Members of Tilasite Group:
ArsenatrotitaniteNaTi(AsO4)OMon. 2/m : B2/b
DurangiteNaAl(AsO4)FMon. 2/m : B2/b
IsokiteCaMg(PO4)FMon. 2/m : B2/b
KononoviteNaMg(SO4)FMon. 2/m : B2/b
LacroixiteNaAl(PO4)FMon. 2/m : B2/b
PanasqueiraiteCaMg(PO4)(OH)Mon.
ReznitskyiteCaMg(VO4)FMon. 2/m : B2/b
TilasiteCaMg(AsO4)FMon.
Forms a series with:

Common AssociatesHide

Associations Based on Photo Data:
12 photos of Maxwellite associated with TripuhyiteFe3+Sb5+O4
2 photos of Maxwellite associated with PseudobrookiteFe3+2Ti4+O5
2 photos of Maxwellite associated with Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
1 photo of Maxwellite associated with QuartzSiO2
1 photo of Maxwellite associated with AdeliteCaMg(AsO4)(OH)

Related Minerals - Strunz-mindat GroupingHide

8.BH.PeterchiniteZn3Zn2(OH)6As[O3(OH)3]Mon. 2/m : B2/m
8.BH.ReznitskyiteCaMg(VO4)FMon. 2/m : B2/b
8.BH.PlumbogottlobitePbMg(VO4)(OH)Orth. mmm(2/m2/m2/m) : Pnma
8.BH.CuprozheshengitePb4CuZn2(AsO4)2(PO4)2(OH)2Tric. 1 : P1
8.BH.ZheshengitePb4ZnZn2(AsO4)2(PO4)2(OH)2Tric. 1 : P1
8.BH.CrimsonitePbFe3+2(PO4)2(OH)2Orth. mmm(2/m2/m2/m) : Cccm
8.BH.05ThadeuiteCa(Mg,Fe2+)3(PO4)2(OH,F)2Orth. 222 : C2221
8.BH.10PanasqueiraiteCaMg(PO4)(OH)Mon.
8.BH.10IsokiteCaMg(PO4)FMon. 2/m : B2/b
8.BH.10LacroixiteNaAl(PO4)FMon. 2/m : B2/b
8.BH.10ArsenatrotitaniteNaTi(AsO4)OMon. 2/m : B2/b
8.BH.10DurangiteNaAl(AsO4)FMon. 2/m : B2/b
8.BH.10KononoviteNaMg(SO4)FMon. 2/m : B2/b
8.BH.15DrugmanitePb2Fe3+(PO4)(PO3OH)(OH)2Mon. 2/m : P21/b
8.BH.20Nigelcookite PbFe2+2V3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20Plumbojohntomaite PbFe2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20CirroliteCa3Al2(PO4)3(OH)3 (?)
8.BH.20PenikisiteBa(Mg,Fe2+,Ca)2Al2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20PerloffiteBa(Mn2+,Fe2+)2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20Bjarebyite Group
8.BH.20StrontioperloffiteSrMn2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20PlumboperloffitePbMn2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20JohntomaiteBaFe2+2Fe3+2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20Bjarebyite(Ba,Sr)(Mn2+,Fe2+,Mg)2Al2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.20KulaniteBa(Fe2+,Mn2+,Mg)2(Al,Fe3+)2(PO4)3(OH)3Mon. 2/m : P21/m
8.BH.25BertossaiteLi2CaAl4(PO4)4(OH)4Orth. mmm(2/m2/m2/m)
8.BH.25NatropalermoiteNa2SrAl4(PO4)4(OH)4Orth. mmm(2/m2/m2/m)
8.BH.25PalermoiteLi2SrAl4(PO4)4(OH)4Orth. mmm(2/m2/m2/m)
8.BH.30SewarditeCaFe3+2(AsO4)2(OH)2Orth. mmm(2/m2/m2/m) : Cccm
8.BH.30CarminitePbFe3+2(AsO4)2(OH)2Orth. mmm(2/m2/m2/m) : Cccm
8.BH.35AdeliteCaMg(AsO4)(OH)Orth. 222 : P212121
8.BH.35DuftitePbCu(AsO4)(OH)Orth. 222 : P212121
8.BH.35CobaltaustiniteCaCo(AsO4)(OH)Orth. 222 : P212121
8.BH.35NickelaustiniteCaNi(AsO4)(OH)Orth. 222 : P212121
8.BH.35GabrielsonitePbFe3+(As3+O3)OOrth. mm2 : Pmc21
8.BH.35ConichalciteCaCu(AsO4)(OH)Orth. 222 : P212121
8.BH.35ArsendescloizitePbZn(AsO4)(OH)Orth. 222 : P212121
8.BH.35'Duftite-alpha'PbCu(AsO4)(OH)
8.BH.35GottlobiteCaMg(VO4)(OH)Orth. 222 : P212121
8.BH.35AustiniteCaZn(AsO4)(OH)Orth. 222 : P212121
8.BH.35HermannroseiteCaCu(PO4)(OH)Orth. 222 : P212121
8.BH.35TangeiteCaCu(VO4)(OH)Orth. 222 : P212121
8.BH.40ČechitePbFe2+(VO4)(OH)Orth. mmm(2/m2/m2/m)
8.BH.40Khorixasite(Bi0.670.33)Cu(VO4)(OH)Mon. 2/m : P2/m
8.BH.40MottramitePbCu(VO4)(OH)Orth. mmm(2/m2/m2/m) : Pnma
8.BH.40DescloizitePbZn(VO4)(OH)Orth. mmm(2/m2/m2/m) : Pnma
8.BH.40PyrobelonitePbMn2+(VO4)(OH)Orth. mmm(2/m2/m2/m) : Pnma
8.BH.45BayldonitePbCu3(AsO4)2(OH)2Mon. 2/m : B2/b
8.BH.45VésigniéiteBaCu3(VO4)2(OH)2Mon. 2/m : B2/m
8.BH.50PaganoiteNiBi(AsO4)OTric. 1 : P1
8.BH.55JagoweriteBaAl2(PO4)2(OH)2Tric.
8.BH.55HarrisoniteCa(Fe2+,Mg)6(PO4)2(SiO4)2Trig. 3m(32/m) : R3m
8.BH.60AttakoliteCaMn2+Al4(SiO3OH)(PO4)3(OH)4Mon. 2/m : B2/m
8.BH.65LeningraditePbCu3(VO4)2ClOrth. mmm(2/m2/m2/m) : Ibam
8.BH.70KatiarsiteKTiO(AsO4)Orth. mm2 : Pna21
8.BH.70YurgensoniteK2SnTiO2(AsO4)2Orth. mm2 : Pna21
8.BH.75MelanarsiteK3Cu7Fe3+O4(AsO4)4Mon. 2/m : B2/b
8.BH.80EvseeviteNa2Mg(AsO4)FOrth. mmm(2/m2/m2/m) : Pbcn
8.BH.80MoraskoiteNa2Mg(PO4)FOrth. mmm(2/m2/m2/m) : Pbcn
8.BH.85PiccoliiteNaCaMn3+2(AsO4)2O(OH)Orth. mmm(2/m2/m2/m) : Pbcm

Fluorescence of MaxwelliteHide

Not fluorescent in UV.

Other InformationHide

Notes:
Slowly soluble in HCl and HNO3, and readily soluble in hot H2SO4.
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 MaxwelliteHide

References for MaxwelliteHide

Localities for MaxwelliteHide

Showing 4 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.
USA (TL)
 
  • New Mexico
    • Catron County
      • Taylor Creek Mining District
- (1989) +2 other references
    • Sierra County
Northrop et al. (1996)
Northrop et al. (1996)
Northrop et al. (1996)
 
and/or  
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