Vote for your favorite mineral in #MinCup26! - Halite vs. Chrysocolla
It's blue skies ahead as multicoloured cubes of Halite are up against the bubbly cool-toned Chrysocolla.
Log InRegister
Quick Links : The Mindat ManualThe Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsThe Rock H. Currier Digital LibraryGeologic TimeExplore Fossils
Minerals by PropertiesMinerals by ChemistryMineral Visual ExplorerAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral QuizTime Machine
Photo SearchPhoto GalleriesSearch by ColorPhoto Colour ExplorerNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Ferrobobfergusonite

A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
Formula:
Na2Fe2+5Fe3+Al(PO4)6
Colour:
deep green-brown
Lustre:
Vitreous
Hardness:
5
Specific Gravity:
3.68
Crystal System:
Monoclinic
Isostructural with:
Bobfergusonite
The ferrous iron analogue of bobfergusonite.

The cations located at the M sites are strongly ordered, over the six available sites; M1, M2, M3, and M4 are mainly dominantly by Fe2+, while M5 and M6 by Fe3+ and Al, respectively.


Hide all sections | Show all sections

Unique IdentifiersHide

Mindat ID:
51833
Long-form identifier:
mindat:1:1:51833:8

IMA Classification of FerrobobfergusoniteHide

Classification of FerrobobfergusoniteHide

Strunz-mindat (2026):
8.AC.07

8 : PHOSPHATES, ARSENATES, VANADATES
A : Phosphates, etc. without additional anions, without H2O
C : With medium-sized and large cations

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

Pronunciation of FerrobobfergusoniteHide

Pronunciation:
PlayRecorded byCountry
Jolyon RalphUnited Kingdom

Physical Properties of FerrobobfergusoniteHide

Lustre:
Vitreous
Transparency:
Transparent
Colour:
Deep green-brown
Streak:
Pale green-yellow
Hardness:
5 on Mohs scale
Comment:
ca.
Tenacity:
Brittle
Cleavage:
Perfect
on {010}
Parting:
not observed (macroscopically)
Density:
3.68(1) g/cm3 (Measured)    3.69 g/cm3 (Calculated)

Optical Data of FerrobobfergusoniteHide

Type:
Biaxial (+)
RI values:
nα = 1.698(2) nβ = 1.705(2) nγ = 1.727(2)
2V:
Measured: 65° (2), Calculated: 60°
Max. Birefringence:
δ = 0.029
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 biaxial acute bisectrix (Bxa) interference figure - the conoscopic view for a grain cut perpendicular to the acute bisectrix, using this mineral's 2V. The two small white dots mark the melatopes - the points where the two optic axes emerge - and are shown only when they fall within the field of view. The coloured bands are isochromatics, and the dark bands are isogyres.

Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.
Dispersion:
very strong, r > v
Comments:
X = yellowish brown, Y = brown, and Z = deep brown
Comments:
optical axes orientation: α ∧ X = 16°, β = Y

Chemistry of FerrobobfergusoniteHide

Mindat Formula:
Na2Fe2+5Fe3+Al(PO4)6
Element Weights:
Element% weight
O39.268 %
Fe34.266 %
P19.005 %
Na4.702 %
Al2.759 %

Calculated from ideal end-member formula.
O
Fe
P
Na
Al
Elements listed:
Al, Fe, Na, O, P - search for minerals with similar chemistry

Crystallography of FerrobobfergusoniteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/c
Setting:
P21/c
Cell Parameters:
a = 12.7156(3) Å, b = 12.3808(3) Å, c = 10.9347(3) Å
β = 97.3329(10)°
Ratio:
a:b:c = 1.027 : 1 : 0.883
Unit Cell V:
1,707.36 ų (Calculated from Unit Cell)
Twinning:
not observed (macroscopically)

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 4b: Highly evolved igneous rocks>3.0
34 : Complex granite pegmatites

Type Occurrence of FerrobobfergusoniteHide

Type Locality:
ⓘ Victory Mine, Custer, Custer Mining District, Custer County, South Dakota, USA
General Appearance of Type Material:
as broken pieces of blocky or tabular habit, where single crystals are up to 0.9 × 0.7 × 0.4 mm in size
Place of Conservation of Type Material:
Type material is deposited in the collections of the Mineral Museum of the University of Arizona, Tucson, USA, catalogue # 21437, and the RRUFF Project, deposition # R140993
Associated Minerals at Type Locality:
Arrojadite-(KFe)FerrowyllieiteFillowiteMuscoviteQuartz
Schorl
Reference:
Yang, Hexiong, Yong, Tommy, Downs, Robert T. (2021) Ferrobobfergusonite, □Na2Fe2+5Fe3+Al(PO4)6, a new mineral of the bobfergusonite group from the Victory Mine, Custer County, South Dakota, USA. The Canadian Mineralogist, 59 (3) 617-627 doi:10.3749/canmin.2000064

Synonyms of FerrobobfergusoniteHide

Other Language Names for FerrobobfergusoniteHide

Relationship of Ferrobobfergusonite to other SpeciesHide

Member of:
Bobfergusonite Group > Alluaudite Supergroup
Other Members of Bobfergusonite Group:
BobfergusoniteNa2Mn5FeAl(PO4)6Mon. 2/m : P21/c

Related Minerals - Strunz-mindat GroupingHide

8.AC.'Crocobelonite-1M'CaFe3+2O(PO4)2Mon. 2/m : P21/m
8.AC.MagnesioqingheiiteNa2Mg(MgAl)(PO4)3Mon. 2/m
8.AC.ManganobadaloviteNaNaMn(MgFe3+)(AsO4)3Mon. 2/m : B2/b
8.AC.Changesite-(Y)(Ca8Y)◻Fe2+(PO4)7Trig. 3m : R3c
8.AC.Babunaite-(Nd)NdAsO4Tet. 4/m : I41/a
8.AC.CrocobeloniteCaFe3+2O(PO4)2Orth. mmm(2/m2/m2/m) : Pnma
8.AC.WopmayiteCa6Na3◻Mn(PO4)3(PO3OH)4 Trig. 3m : R3c
8.AC.BeershevaiteCaFe3+3(PO4)3OMon. 2/m : P21/m
8.AC.Epiebnerite(NH4)Zn(PO4)Mon. 2 : P21
8.AC.Ebnerite(NH4)Zn(PO4)Hex. 6 : P63
8.AC.XDyrnaesite-(La)Na8Ce4+(La,REE)2(PO4)6Orth. mmm(2/m2/m2/m) : Pnma
8.AC.EdtolliteK2NaCu5Fe3+O2(AsO4)4Tric. 1 : P1
8.AC.AngarfiteNaFe3+5(PO4)4(OH)4 · 4H2O Orth. 222 : C2221
8.AC.KabaloviteFe2+3Fe3+4(PO4)6Tric. 1 : P1
8.AC.Nazarchukite Ca2NiFe3+2(PO4)4Orth. mmm(2/m2/m2/m) : Pbca
8.AC.CalciohatertiteNaNaCa(CaFe3+)(AsO4)3Mon. 2/m : B2/b
8.AC.AlumoedtolliteK2NaCu5AlO2(AsO4)4Tric. 1 : P1
8.AC.02GrigorieviteCu3Fe3+2Al2(VO4)6Tric. 1 : P1
8.AC.02KoksharoviteCaMg2Fe3+4(VO4)6Tric. 1 : P1
8.AC.02ZiminaiteFe3+ 6 (VO4)6Tric. 1 : P1
8.AC.05HatertiteNa2(Ca,Na)(Fe3+,Cu)2(AsO4)3Mon. 2/m : B2/b
8.AC.05ErikapohliteCu3(Zn,Cu,Mg)4Ca2(AsO4)6 · 2H2OMon. 2/m : B2/m
8.AC.05'Unnamed (Na-Mg Arsenate Hydroxyarsenate)'NaMg3(AsO4)(AsO3OH)2Mon. 2/m : B2/b
8.AC.05'Unnamed (Na-Zn-H Arsenate Hydroxyarsenate)'Na(Na0.6Zn0.4)Zn2(H0.6AsO4)(AsO3OH)2Mon. 2/m : B2/b
8.AC.05CalciojohilleriteNaCaMg3(AsO4)3Mon. 2/m : B2/b
8.AC.05Magnesiohatertite(Na,Ca)2Ca(Mg,Fe3+)2(AsO4)3Mon. 2/m : B2/b
8.AC.05 va'Alluaudite-Na[]'◻4Na4Mn2+4Fe3+8(PO4)12Mon. 2/m : B2/b
8.AC.05 va'Alluaudite-Ca[]'◻4Ca4Mn2+4Fe3+8(PO4)12Mon. 2/m : B2/b
8.AC.05 va'Ferroalluaudite-NaNa'Na4Na4Fe2+4Fe3+8(PO4)12Mon. 2/m : B2/m
8.AC.05'Hagendorfite-NaNa'NaNaFe2+(Mn2+,Mn3+)(PO4)3 (?)Mon. 2/m : B2/b
8.AC.05O'DanieliteNa(Zn,Mg)3(AsO4)(AsO3OH)2Mon. 2/m : B2/b
8.AC.05HowardevansiteNaCuFe2(VO4)3Tric. 1 : P1
8.AC.05KhrenoviteNa3Fe3+2(AsO4)3Mon. 2/m : B2/b
8.AC.05ZincobradaczekiteNaZn2Cu2(AsO4)3Mon. 2/m : B2/b
8.AC.05ParaberzeliiteNaCa2Mg2(AsO4)3Mon. 2/m : B2/b
8.AC.05BadaloviteNa2Mg2Fe(AsO4)3Mon. 2/m : B2/b
8.AC.05MagnesiocanutiteNaMnMg2[AsO4]2[AsO2(OH)2]Mon. 2/m : B2/b
8.AC.05ManganohatertiteNaNaCa(MnFe3+)(AsO4)3Mon. 2/m : B2/b
8.AC.05CamanchacaiteNaCaMg2[AsO4][AsO3(OH)]2Mon. 2/m : B2/b
8.AC.07ZhanghuifeniteNa3Mn4Mg2Al(PO4)6Mon. 2/m
8.AC.10HagendorfiteNaCaMn2+Fe2+2(PO4)3Mon. 2/m : B2/b
8.AC.10'Ferrohagendorfite'NaCaFe2+Fe2+2(PO4)3Mon.
8.AC.10JohilleriteNa(Mg,Zn)3Cu(AsO4)3Mon. 2/m : B2/b
8.AC.10VaruliteNaCaMn2+Mn2+2(PO4)3Mon. 2/m : B2/b
8.AC.10NickenichiteNa0.8Ca0.4Cu0.4(Mg,Fe)3(AsO4)3Mon. 2/m : B2/b
8.AC.10ArseniopleiteNaCaMnMn2(AsO4)3Mon. 2/m
8.AC.10GroatiteNaCaMn2(PO4)[PO3(OH)]2Mon. 2/m : B2/b
8.AC.10Alluaudite(Na,Ca)Mn2+(Fe3+,Mn2+,Fe2+,Mg)2(PO4)3Mon. 2/m : B2/b
8.AC.10BradaczekiteNaCu4(AsO4)3Mon. 2/m : B2/b
8.AC.10Caryinite(Na,Pb)(Ca,Na)CaMn2+2(AsO4)3Mon. 2/m
8.AC.10Ferroalluaudite(Na,Ca)Fe2+(Fe3+,Mn2+,Fe2+)2(PO4)3Mon. 2/m : B2/b
8.AC.10Maghagendorfite(Na,◻)MgMn2+(Fe2+,Fe3+)2(PO4)3Mon. 2/m
8.AC.15Ferrowyllieite(Na,Ca,Mn)(Fe,Mn)(Fe,Fe,Mg)Al(PO4)3Mon. 2/m : P21/c
8.AC.15QingheiiteNaNaMn2+(MgAl)(PO4)3Mon. 2/m : P21/c
8.AC.15Rosemaryite(Na,Ca,Mn)(Mn,Fe2+)(Fe3+,Mg)Al(PO4)3Mon. 2/m : P21/c
8.AC.15FerroqingheiiteNaNaFe2+(MgAl)(PO4)3Mon. 2/m : P21/m
8.AC.15Ferrorosemaryite◻NaFe2+Fe3+Al(PO4)3Mon. 2/m
8.AC.15BobfergusoniteNa2Mn5FeAl(PO4)6Mon. 2/m : P21/c
8.AC.15Wyllieite(Na,Ca,Mn)(Mn,Fe)(Fe,Mg)Al(PO4)3Mon. 2/m
8.AC.17CzochralskiiteNa4Ca3Mg(PO4)4Orth. mmm(2/m2/m2/m) : Pnma
8.AC.18ManitobaiteNa16Mn2+ 25Al8(PO4)30Mon. m : Pb
8.AC.20MarićiteNaFe2+(PO4)Orth. mmm(2/m2/m2/m) : Pmna
8.AC.25Schäferite(NaCa2)Mg2(VO4)3Iso. m3m(4/m32/m) : Ia3d
8.AC.25Berzeliite(NaCa2)Mg2(AsO4)3Iso. m3m(4/m32/m) : Ia3d
8.AC.25MatyhiteCa18(Ca,◻)2Fe2+2(PO4)14Trig. 3m : R3c
8.AC.25Hedegaardite(Ca,Na)9(Ca,Na)Mg(PO4)6(PO3OH)Trig. 3m : R3c
8.AC.25Manganberzeliite(NaCa2)Mn2+2(AsO4)3Iso. m3m(4/m32/m) : Ia3d
8.AC.25Palenzonaite(NaCa2)Mn2+2(VO4)3Iso. m3m(4/m32/m) : Ia3d
8.AC.30BrianiteNa2CaMg(PO4)2Mon. 2/m : P21/c
8.AC.35Vitusite-(Ce)Na3(Ce,La,Nd)(PO4)2Orth. mm2 : Pca21
8.AC.40Bario-olgite(Ba,Sr)(Na,Sr,REE)2Na(PO4)2 · Trig. 3 : P3
8.AC.40Olgite(Sr,Ba)(Na,Sr,REE)2Na(PO4)2Trig. 3m(32/m) : P3m1
8.AC.45Magnesiochangesite-(Ce)(Ca8Ce)◻Mg(PO4)7Trig. 3m : R3c
8.AC.45TuiteCa3(PO4)2Trig. 3m(32/m) : R3m
8.AC.45FerromerrilliteCa9NaFe2+(PO4)7Trig. 3m : R3c
8.AC.45StrontiowhitlockiteSr9Mg(PO4)6(PO3OH)Trig. 3m : R3c
8.AC.45Magnesiochangesite-(Y)(Ca8Y)◻ Mg(PO4)7Trig. 3m : R3m
8.AC.45Changesite-(Ce)(Ca8Ce)◻Fe2+(PO4)7Trig. 3m : R3c
8.AC.45MerrilliteCa9NaMg(PO4)7Trig. 3m : R3m
8.AC.45WhitlockiteCa9Mg(PO4)6(PO3OH)Trig. 3m : R3c
8.AC.47IwateiteNa2BaMn(PO4)2Trig. 3 : P3
8.AC.47OzerovaiteNa2KAl3(AsO4)4Orth. mmm(2/m2/m2/m) : Cmca
8.AC.47YurmariniteNa7(Fe3+,Mg,Cu)4(AsO4)6Trig. 3m(32/m) : R3c
8.AC.47PansneriteK3Na3(Fe3+,Al)6(AsO4)8Orth. mmm(2/m2/m2/m)
8.AC.47AnatolyiteNa6(Ca,Na)(Mg,Fe3+)3Al(AsO4)6Trig. 3m(32/m) : R3c
8.AC.50FillowiteNa3CaMn2+11(PO4)9Trig. 3 : R3
8.AC.50GalileiiteNa3Fe2+Fe2+11(PO4)9Trig. 3 : R3
8.AC.50JohnsomervilleiteNa3CaFe11(PO4)9Trig. 3 : R3
8.AC.50XenophylliteNa4Fe2+7(PO4)6Tric. 1 : P1
8.AC.50UdinaiteNaMg4(VO4)3Tet. 42m : I42d
8.AC.50ArsenudinaiteNaMg4(AsO4)3Tet. 42m : I42d
8.AC.50ChladniiteNa3CaMg11(PO4)9Trig. 3 : R3
8.AC.52Lasnierite(Ca,Sr)(Mg,Fe2+)2Al(P[O,F]4)3Orth. mmm(2/m2/m2/m) : Pbcn
8.AC.55PharmazinciteKZnAsO4Hex. 6 : P63
8.AC.57ZubkovaiteCa3Cu3(AsO4)4Mon. 2 : B2
8.AC.60KosnariteKZr2(PO4)3Trig. 3m(32/m) : R3c
8.AC.65Panethite(Na,Ca)2(Mg,Fe2+)2(PO4)2Mon. 2/m : P21/c
8.AC.70StanfielditeCa4Mg5(PO4)6Mon.
8.AC.75RonneburgiteK2MnV4O12Mon. 2/m
8.AC.80TillmannsiteAg3Hg[(V,As)O4]Tet. 4 : I4
8.AC.85FilatoviteK(Al,Zn)2(As,Si)2O8Mon. 2/m

Other InformationHide

Notes:
calc. compatibility index based on the empirical formula: 0.017 (superior)
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 FerrobobfergusoniteHide

References for FerrobobfergusoniteHide

Localities for FerrobobfergusoniteHide

Showing 2 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.
Hide all sections | Show all sections

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.
Spain
 
  • Castile and Leon
    • Salamanca
      • Golpejas
        • Golpejas Mining group
Calvo Rebollar et al. (2022)
USA (TL)
 
  • South Dakota
    • Custer County
      • Custer Mining District
        • Custer
Hålenius et al. (2017) +1 other reference
Quick NavTopUnique IdentifiersIMA Classification Classification Mineral SymbolsPronunciation Physical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesRelationshipsStrunz-MindatOther InformationInternet Links References Localities Locality List
 
and/or  
Mindat.org® is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Mindat® and mindat.org® are registered trademarks of the Hudson Institute of Mineralogy.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2026, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph and Ida Chau.
Content on this site may not be used to train, fine-tune, or otherwise develop artificial intelligence or machine learning models without prior written permission - see our Terms & Conditions.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: September 23, 2026 08:23:57 Page updated: September 6, 2026 22:27:22
Go to top of page