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Robertsite

A valid IMA mineral species
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02775290017271926188314.jpg
Robertsite, etc.

Tip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
02925040017871398369695.jpg
Robertsite, etc.

Tip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
02291440017271926286470.jpg
Robertsite

Tip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
04638660017865251559505.jpg
Robertsite, etc.

Tip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
07848620017869727225581.jpg
Robertsite, etc.

Tip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
02291440017271926286470.jpg
Robertsite

Tip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
02775290017271926188314.jpg
Robertsite, etc.

Tip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
02925040017871398369695.jpg
Robertsite, etc.

Tip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
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About RobertsiteHide

02766910017271926347500.jpg
Willard "Bill" Lincoln Roberts
Formula:
Ca2Mn3+3(PO4)3O2 · 3H2O
Colour:
Red, red-brown, deep red, bronzy brown, black
Lustre:
Waxy, Greasy, Pearly
Hardness:
3½
Specific Gravity:
3.13
Crystal System:
Monoclinic
Name:
Named in 1974 by Paul Brian Moore and Jun Ito in honor of Willard "Bill" Lincoln Roberts [February 12, 1923 Epworth, Iowa, USA - March 23, 1987 Rapid City, South Dakota, USA], professor of mineralogy and curator of the South Dakota School of Mines mineral museum. Bill was strongly influenced by the phosphate mineral bearing granite pegmatites of the nearby Black Hill and collaborated with many mineralogists, including Mary Mrose, Paul Moore, and Jun Ito and through this collaboration about 15-20 phosphates minerals were described by various authors. Bill was senior author of both the Mineralogy of the Black Hills and the Encyclopedia of Minerals (first edition).
Dimorph of:
Pararobertsite
Isostructural with:
Arseniosiderite
Brown to dark brown coatings, usually fine-grained, but sometimes crystallized with densely packed pseudohexagonal platy, columnar, or fibrous crystals.

Much more common than its dimorph pararobertsite.

The phosphate analogue of georgeliuite.


Unique IdentifiersHide

Mindat ID:
3431
Long-form identifier:
mindat:1:1:3431:5

IMA Classification of RobertsiteHide

Classification of RobertsiteHide

Strunz-mindat (2026):
8.DH.30

8 : PHOSPHATES, ARSENATES, VANADATES
D : Phosphates, etc. with additional anions, with H2O
H : With large and medium-sized cations, (OH, etc.):RO4 < 1:1
Dana 8th ed.:
42.8.4.2

42 : HYDRATED PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
8 : (AB)5(XO4)3Zq·xH2O
Hey's CIM Ref.:
19.12.6

19 : Phosphates
12 : Phosphates of Mn

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

Physical Properties of RobertsiteHide

Lustre:
Waxy, Greasy, Pearly
Transparency:
Translucent
Comment:
Bright relections on basal sections
Colour:
Red, red-brown, deep red, bronzy brown, black
Streak:
Red-brown
Hardness:
3½ on Mohs scale
Tenacity:
Waxy
Cleavage:
Very Good
{100}
Fracture:
Micaceous
Density:
3.13 g/cm3 (Measured)    3.05 g/cm3 (Calculated)

Optical Data of RobertsiteHide

Type:
Biaxial (-)
RI values:
nα = 1.775 nβ = 1.820 nγ = 1.820
2V:
Measured: 8°
Birefringence:
0.045
Max. Birefringence:
δ = 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:
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:
relatively weak
Optical Extinction:
X ~ ⊥ {100}
Pleochroism:
Strong
Comments:
X pale red to pink Y,Z deep red brown

Chemistry of RobertsiteHide

Mindat Formula:
Ca2Mn3+3(PO4)3O2 · 3H2O
Element Weights:
Element% weight
O44.159 %
Mn26.759 %
P15.086 %
Ca13.014 %
H0.982 %

Calculated from ideal end-member formula.
O
Mn
P
Ca
H
Elements listed:
Ca, H, Mn, O, P - search for minerals with similar chemistry

Crystallography of RobertsiteHide

Crystal System:
Monoclinic
Class (H-M):
m - Domatic
Space Group:
Bb
Setting:
Bb
Cell Parameters:
a = 17.3400(9) Å, b = 19.4464(10) Å, c = 11.2787(6) Å
β = 96.634(3)°
Ratio:
a:b:c = 0.892 : 1 : 0.58
Unit Cell V:
3777.7 ų
Z:
12
Morphology:
Frequently earthy in coatings. Not rarely scaly or in densely packed crystals in subparallel groupings. Crystals frequently show corrugations and deep striations or notches.
Twinning:
Multiple rotation twins (π/3) perpendicular to {100}
Comment:
Space group Cm, but a non-standard cell was chosen, cfr Andrade et al. (2012)

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0019365RobertsiteAndrade M B, Morrison S M, Di Domizio A J, Feinglos M N, Downs R T (2012) Robertsite, Ca2MnIII3O2(PO4)*3H2O Acta Crystallographica E68 i74-i752012Tip Top mine, Custer County, South Dakota, USA0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
8.63 Å(100)
5.61 Å(50)
3.27 Å(40)
2.88 Å(30)
2.75 Å(60)
2.59 Å(40)
2.16 Å(30)
1.623 Å(50)
Comments:
26-1067

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Near-surface Processes
21 : Chemically precipitated carbonate, phosphate, iron formations
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
48 : Soil leaching zone minerals<0.6
52 : Guano- and urine-derived minerals<0.4
53 : Other minerals with taphonomic origins<0.4

Type Occurrence of RobertsiteHide

Synonyms of RobertsiteHide

Other Language Names for RobertsiteHide

German:Robertsit
Spanish:Robertsita

Relationship of Robertsite to other SpeciesHide

Member of:
Mitridatite Group
Other Members of Mitridatite Group:
ArseniosideriteCa2Fe3+3(AsO4)3O2 · 3H2OMon. 2/m : B2/b
GeorgeliuiteCa2Mn3+3O2(AsO4)3(H2O)2 · H2OMon. m : Bm
KolfaniteCa2Fe3+3O2(AsO4)3 · 2H2OMon.
MitridatiteCa2Fe3+3(PO4)3O2 · 3H2OMon. 2/m : B2/b
Forms a series with:
ArseniosideriteArseniosiderite-Robertsite Series

Common AssociatesHide

Associations Based on Photo Data:
30 photos of Robertsite associated with MontgomeryiteCa4MgAl4(PO4)6(OH)4 · 12H2O
27 photos of Robertsite associated with WhitlockiteCa9Mg(PO4)6(PO3OH)
13 photos of Robertsite associated with LeucophosphiteKFe3+2(PO4)2(OH) · 2H2O
13 photos of Robertsite associated with CollinsiteCa2Mg(PO4)2 · 2H2O
12 photos of Robertsite associated with Rockbridgeite(Fe2+0.5Fe3+0.5)2Fe3+3(PO4)3(OH)5
9 photos of Robertsite associated with EnglishiteK3Na2Ca10Al15(PO4)21(OH)7 · 26H2O
8 photos of Robertsite associated with BermaniteMn2+Mn3+2(PO4)2(OH)2 · 4H2O
8 photos of Robertsite associated with MitridatiteCa2Fe3+3(PO4)3O2 · 3H2O
8 photos of Robertsite associated with HureauliteMn2+5(PO3OH)2(PO4)2 · 4H2O
8 photos of Robertsite associated with RoscheriteCa2Mn2+5Be4(PO4)6(OH)4 · 6H2O

Related Minerals - Strunz-mindat GroupingHide

8.DH.Thebaite-(NH4)(NH4)3Al(C2O4)(PO3OH)2(H2O)Mon. 2/m : P21/b
8.DH.Whiteite-(MnMnMn)Mn2+Mn2+Mn2+2Al2(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.Ammoniotinsleyite(NH4)Al2(PO4)2(OH) · 2H2OMon. 2/m : P21/m
8.DH.Bergbauerite(H2O)2Mn2(Fe2Ti)(PO4)4(OH)2(H2O)10 · 4H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.Dendoraite-(NH4)(NH4)2NaAl(C2O4)(PO3OH)2(H2O)2Mon. 2/m
8.DH.Rowleyite[Na(NH4,K)9Cl4][V5+,4+2(P,As)O8]6 · n[H2O,Na,NH4,K,Cl]Iso.
8.DH.HochleitneriteMn2Ti3(PO4)4O2(H2O)2 · 14H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.Whiteite-(CaMnFe)CaMnFe2Al2(PO4)4(OH)2 · 8H2OMon. 2/m
8.DH.05MinyuliteKAl2(PO4)2F · 4H2OOrth. mm2 : Pba2
8.DH.10LeucophosphiteKFe3+2(PO4)2(OH) · 2H2OMon. 2/m : P21/b
8.DH.10TinsleyiteKAl2(PO4)2(OH) · 2H2OMon.
8.DH.10Spheniscidite(NH4,K)(Fe3+,Al)2(PO4)2(OH) · 2H2OMon. 2/m
8.DH.15Jahnsite-(CaMnFe){Ca}{Mn2+}{Fe2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(NaMnMn){Na}{Mn2+}{(Mn2+,Fe3+)2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(CaMnMg){Ca}{Mn2+}{(Mg,Fe2+)2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(CaMnMn){Ca}{Mn2+}{Mn2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Whiteite-(MnMnMg)MnMnMg2Al2(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(CaMnZn){Ca}{Mn2+}{Zn2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(MnMnMg){Mn2+}{Mn2+}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(MnMnFe){Mn2+}{Mn2+}{Fe2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15'Jahnsite-(CaFeFe)'{Ca}{Fe2+}{Fe2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon.
8.DH.15Rittmannite{(Mn2+,Ca)}{Mn2+}{(Fe2+,Mn2+,Mg)2}{(Al,Fe3+)2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15KeckiteCaMn2+(Fe3+Mn2+)Fe3+2(PO4)4(OH)3 · 7H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(NaMnMg){(Na,Ca)}{(Mn2+,Fe3+)}{(Mg,Fe3+)2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15'Jahnsite-(CaMgMg)'{Ca}{Mg}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2O
8.DH.15Jahnsite-(MnMnZn){Mn2+}{Mn2+}{Zn2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Whiteite-(CaMgMg)CaMg3Al2(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Whiteite-(CaFeMg){Ca}{(Fe2+,Mn2+)}{Mg2}{Al2}(PO4)4(OH)2 · 8H2OMon. 2/m : P21/b
8.DH.15Whiteite-(CaMnMg){Ca}{Mn2+}{Mg2}{Al2}(PO4)4(OH)2 · 8H2OMon. 2/m
8.DH.15Whiteite-(MnFeMg){(Mn2+,Ca)}{(Fe2+,Mn2+)}{Mg2}{Al2}(PO4)4(OH)2 · 8H2OMon. 2/m : P21/b
8.DH.15Jahnsite-(MnMnMn){Mn2+}{Mn2+}{Mn2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P21/b
8.DH.15'Kaluginite'(Mn2+,Ca)MgFe3+(PO4)2(OH) · 4H2OOrth.
8.DH.15Jahnsite-(CaFeMg){Ca}{Fe2+}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Whiteite-(CaMnMn){Ca}{Mn2+}{Mn2}{Al2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(NaFeMg){Na}{Fe3+}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.20SegeleriteCa2 Mg2 Fe3+2(PO4)4(OH)2 · 8H2OOrth. mmm(2/m2/m2/m) : Pcca
8.DH.20Lun'okite(Mn,Ca)(Mg,Fe,Mn)Al(PO4)2OH · 4H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.20Manganosegelerite(Mn2+,Ca)(Mn2+,Fe2+,Mg)Fe3+(PO4)2(OH) · 4H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.20WilhelmvierlingiteCaMnFe3+(PO4)2(OH) · 2H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.20JuonniiteCaMgSc(PO4)2(OH) · 4H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.20OveriteCaMgAl(PO4)2(OH) · 4H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.25CalcioferriteCa4MgFe3+4(PO4)6(OH)4 · 12H2OMon. 2/m : B2/b
8.DH.25ZodaciteCa4Mn2+Fe3+4(PO4)6(OH)4 · 12H2OMon.
8.DH.25FanfaniiteCa4Mn2+Al4(PO4)6(OH)4 · 12H2OMon. 2/m : B2/b
8.DH.25KingsmountiteCa3Mn2+FeAl4(PO4)6(OH)4 · 12H2OTric. 1 : P1
8.DH.25MontgomeryiteCa4MgAl4(PO4)6(OH)4 · 12H2OMon. 2 : B2
8.DH.30PararobertsiteCa2Mn3+3(PO4)3O2 · 3H2OMon. 2/m : P21/b
8.DH.30ArseniosideriteCa2Fe3+3(AsO4)3O2 · 3H2OMon. 2/m : B2/b
8.DH.30Sailaufite(Ca,Na,◻)2Mn3+3(AsO4)2(CO3)O2 · 3H2OMon. m : Bm
8.DH.30MitridatiteCa2Fe3+3(PO4)3O2 · 3H2OMon. 2/m : B2/b
8.DH.30KolfaniteCa2Fe3+3O2(AsO4)3 · 2H2OMon.
8.DH.35MantienneiteKMg2Al2Ti(PO4)4(OH)3 · 15H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.35Sperlingite (H2O)K(Mn2+Fe3+)(Al2Ti)(PO4)4[O(OH)] [(H2O)9(OH)] · 4H2OMon. 2/m : P21/b
8.DH.35PaulkerriteK(Mg,Mn2+)2(Fe3+,Al,Ti,Mg)2Ti(PO4)4(OH)3 · 15H2OMon. m
8.DH.35Hydroxylbenyacarite(H2O)2Mn2(Ti2Fe)(PO4)4[O(OH)](H2O)10 · 4H2O Orth. mmm(2/m2/m2/m) : Pbca
8.DH.35MacraeiteK(H2O)Mn2(Fe2Ti)(PO4)4[O(OH)](H2O)10 · 4H2OMon. 2/m : P21/b
8.DH.35Benyacarite(H2O)2Mn2Ti2Fe3+(PO4)4(OF)(H2O)10 · 4H2OOrth. mmm(2/m2/m2/m) : Pbca
8.DH.35Fluormacraeite [(H2O)K]Mn2(Fe2Ti)(PO4)4(OF)(H2O)10 · 4H2OMon. 2/m : P21/b
8.DH.40XanthoxeniteCa4Fe3+2(PO4)4(OH)2 · 3H2OTric. 1 : P1
8.DH.45MahnertiteNaCu3(AsO4)2Cl · 5H2OTet. 4/mmm(4/m2/m2/m) : I4/mmm
8.DH.50AndyrobertsiteKCdCu5(AsO4)4(H2AsO4) · 2H2OMon. 2/m : P21/m
8.DH.50CalcioandyrobertsiteKCaCu5(AsO4)4(H2AsO4) · 2H2OMon. 2/m : P21/m
8.DH.55EnglishiteK3Na2Ca10Al15(PO4)21(OH)7 · 26H2OMon. 2/m
8.DH.60BouazzeriteBi6(Mg,Co)11Fe3+14(AsO4)18(OH)4O12 · 86H2OMon. 2/m
8.DH.65GalliskiiteCa4Al2(PO4)2F8 · 5H2OTric. 1 : P1
8.DH.70JoteiteCa2CuAl(AsO4)[AsO3(OH)]2(OH)2 · 5H2OTric. 1 : P1
8.DH.75KampeliteBa6Mg3Sc8(PO4)12(OH)6 · 7H2OOrth. mmm(2/m2/m2/m) : Pnma
8.DH.80KapundaiteNaCaFe4(PO4)4(OH)3 · 5H2OTric. 1 : P1
8.DH.85VaniniiteCa2Mn2+3Mn3+2O2(AsO4)4 · 2H2OMon. 2/m : P21/b

Fluorescence of RobertsiteHide

In UV light:
nonfluorescent

Other InformationHide

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 RobertsiteHide

References for RobertsiteHide

Localities for RobertsiteHide

Showing 50 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.
Argentina
 
  • Córdoba Province
    • Pocho Department
      • Parroquia District
Biglia et al. (2021)
  • San Luis Province
    • San Martín Department
Roda-Robles et al. (2012)
Australia
 
  • South Australia
    • Light Regional Council
      • Koonunga
Francis et al. (self published)
    • Pastoral Unincorporated Area
      • Iron Knob
Francis (2010)
  • Western Australia
    • Port Hedland Shire
      • Abydos Station
        • Wodgina
Jacobson et al. (2007)
Brazil
 
  • Minas Gerais
    • Conselheiro Pena
      • Barra do Cuieté
Sergio Varvello collection
Baijot et al. (2014) +1 other reference
Sergio Varvello collection
    • Galiléia
      • Sapucaia do Norte
Roberto Bosi collection.
  • Paraíba
    • Picuí
Sergio Varvello collection
Ethiopia
 
  • Southern Nations Nationalities and Peoples' Region
    • Lower Omo Valley
Rogers et al. (1979)
Europe
 
Berbain et al. (2012)
France
 
  • Auvergne-Rhône-Alpes
    • Allier
      • Vichy
        • Échassières
          • Montmins mining district
Boisson et al. (2000)
  • Occitanie
    • Pyrénées-Orientales
      • Céret
        • Collioure
Berbain et al. (2012)
Germany
 
  • Bavaria
    • Lower Bavaria
      • Regen District
        • Zwiesel
          • Rabenstein
Weiß (1990) +1 other reference
    • Upper Palatinate
      • Neustadt an der Waldnaab District
        • Waidhaus
          • Hagendorf
Van Kauwenbergh et al. (1988) +2 other references
Dill et al. (2008)
  • North Rhine-Westphalia
    • Arnsberg
      • Märkischer Kreis
        • Iserlohn
          • Letmathe
            • Helmke quarry nature reserve
Bender et al. (1994)
Italy
 
  • Sardinia
    • South Sardinia Province
      • Carbonia
        • Barbusi
Baldoni et al. (2013) +2 other references
  • Sicily
    • Syracuse Province
      • Melilli
Audra et al. (2019)
Japan
 
  • Fukuoka Prefecture
    • Fukuoka City
Professor Seiichiro Uehara
Morocco
 
  • Drâa-Tafilalet Region
    • Ouarzazate Province
      • Amerzgane Cercle
        • Ouisselsate Caïdat
Favreau (2012)
  • Marrakesh-Safi Region
    • Rehamna Province
      • Sidi Bou Othmane Cercle
        • Jebilet Mountain (Djebilet Mountain)
          • Sidi Bou Othmane
Favreau (2012)
Namibia
 
  • Erongo Region
    • Dâures Constituency
von Bezing (2007)
Keller (1974)
    • Karibib Constituency
      • Abbabis Farm 70
Förch (1998)
      • Okongava Ost Farm 72
Bezing et al. (2007)
  • ǁKaras Region
    • Berseba Constituency
von Bezing (2007)
    • Karasburg East
von Bezing (2007)
von Bezing (2007)
Philippines
 
  • Visayas
    • Western Visayas Region
      • Palawan Province
        • Palawan Island
          • Puerto Princesa
Onac (2025)
Poland
 
  • Lower Silesian Voivodeship
    • Dzierżoniów County
      • Piława Górna
        • DSS Piława Górna Quarry
Pieczka et al. (2015)
    • Ząbkowice Śląskie County
      • Gmina Ząbkowice Śląskie
        • Szklary
Pieczka et al. (2015) +1 other reference
Portugal
 
  • Viana do Castelo
    • Ponte da Barca
      • Touvedo (São Lourenço e Salvador)
Self-find by Nuno Afonso +1 other reference
  • Viseu
    • Mangualde
      • Mangualde (Mesquitela e Cunha Alta)
Romania
 
  • Maramureș County
    • Baia Mare
Kipfer (1976)
Spain
 
  • Castile and Leon
    • Zamora
      • Villar del Buey
        • Pinilla de Fermoselle
Thailand
 
  • Lamphun Province
Van Kauwenbergh et al. (1988)
USA
 
  • Arizona
    • Yavapai County
Jahns (1952) +1 other reference
        • Independence Gulch
London et al. (1982)
  • California
    • San Diego County
      • Jacumba
        • Tule Mountain (Mount Tule; Tulley Mountain)
Fisher (2002)
  • Maine
    • Oxford County
      • Greenwood
        • Uncle Tom Mountain
Falster et al. (2019)
      • Paris
www.webmineral.com (2000) +1 other reference
  • New Hampshire
    • Cheshire County
Robert Whitmore collection
Czaja (2025)
  • North Carolina
    • Cleveland County
      • Kings Mountain
  • South Dakota
    • Custer County
      • Custer Mining District
        • Custer
Van Kauwenbergh et al. (1988)
        • Fourmile
Moore et al. (1974)
        • Pringle
          • Cicero Peak
Van Kauwenbergh et al. (1988)
    • Pennington County
      • Keystone Mining District
        • Glendale
Smith et al. (2000)
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