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⇱ Kayrobertsonite: Mineral information, data and localities.

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Kayrobertsonite

A valid IMA mineral species

About KayrobertsoniteHide

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👁 05494250017272472564056.jpg
Kay Robertson with Dr. Rob Lavinsky
Formula:
[MnAl2(PO4)2(OH)2(H2O)4] · 2H2O
Colour:
Snow-white
Crystal System:
Triclinic
Name:
Named in honor of Kay Robertson (born Gabriella Katherine Loewi) (b. 23 April 1920, Venice, Italy - d. March 23, 2020, Puget Sound area) of Los Angeles, California, USA, a well known collector, especially of German localities, since the 1950s. She was a founding member of the Southern California Micromineralogists Society.
The OH analogue of nordgauite. Structural topology similar to that of nordgauite, but with double amount of water molecules in the [001] channels.


Unique IdentifiersHide

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Mindat ID:
46697
Long-form identifier:
mindat:1:1:46697:4

IMA Classification of KayrobertsoniteHide

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Approved
IMA Formula:
MnAl2(PO4)2(OH)2 · 6H2O
Approval year:
2015
First published:
2016

Classification of KayrobertsoniteHide

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8.DC.30

8 : PHOSPHATES, ARSENATES, VANADATES
D : Phosphates, etc. with additional anions, with H2O
C : With only medium-sized cations, (OH, etc.):RO4 = 1:1 and < 2:1

Mineral SymbolsHide

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

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

Physical Properties of KayrobertsoniteHide

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Colour:
Snow-white

Optical Data of KayrobertsoniteHide

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Type:
Biaxial (-)
RI values:
nα = 1.530(1) nβ = 1.554(1) nγ = 1.566(1)
2V:
Measured: 70.3° (5), Calculated: 69.6°
Max. Birefringence:
δ = 0.036
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.

Surface Relief:
Moderate
Pleochroism:
Non-pleochroic

Chemistry of KayrobertsoniteHide

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Mindat Formula:
[MnAl2(PO4)2(OH)2(H2O)4] · 2H2O
Element Weights:
Element% weight
O58.054 %
P14.049 %
Mn12.459 %
Al12.238 %
H3.200 %

Calculated from ideal end-member formula.

Crystallography of KayrobertsoniteHide

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Crystal System:
Triclinic
Class (H-M):
1 - Pinacoidal
Space Group:
P1
Setting:
P1
Cell Parameters:
a = 10.049(2) Å, b = 10.205(2) Å, c = 6.083(1) Å
α = 91.79(3)°, β = 99.70(3)°, γ = 98.02(3)°
Ratio:
a:b:c = 0.985 : 1 : 0.596
Unit Cell V:
607.9 ų
Z:
2
Morphology:
Intergrown masses offibrous needles up to 100 μm long and less than 5 μm wide

X-Ray Powder DiffractionHide

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Powder Diffraction Data:
d-spacingIntensity
10.047 Å(100)
9.804 Å(8)
7.629 Å(44)
5.029 Å(12)
4.695 Å(10)
3.023 Å(12)
2.952 Å(10)
2.579 Å(10)

Geological EnvironmentHide

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Paragenetic Mode(s):

Type Occurrence of KayrobertsoniteHide

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General Appearance of Type Material:
intergrown masses of snow-white, soft, finely fibrous needles, less than 5 μm in diameter and no more than 100 μm in length
Place of Conservation of Type Material:
Co-type material is deposited in the mineralogical collections of the Museum Victoria, Melbourne, Victoria, Australia, registered numbers M53379, M53380 and M48795, and the Natural History Museum of Los Angeles County, Los Angeles, CA 90007, USA, registr
Geological Setting of Type Material:
pegmatites

Synonyms of KayrobertsoniteHide

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Other Language Names for KayrobertsoniteHide

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Common AssociatesHide

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Associations Based on Photo Data:
3 photos of Kayrobertsonite associated with Kastningite(Mn2+,Fe2+,Mg)Al2(PO4)2(OH)2 · 8H2O
1 photo of Kayrobertsonite associated with Rittmannite{(Mn2+,Ca)}{Mn2+}{(Fe2+,Mn2+,Mg)2}{(Al,Fe3+)2}(PO4)4(OH)2 · 8H2O
1 photo of Kayrobertsonite associated with StewartiteMn2+Fe3+2(PO4)2(OH)2 · 8H2O
1 photo of Kayrobertsonite associated with StrengiteFePO4 · 2H2O
1 photo of Kayrobertsonite associated with Jahnsite GroupXM1M22M32(H2O)8(OH)2(PO4)4
1 photo of Kayrobertsonite associated with ZwieseliteFe2+2(PO4)F

Related Minerals - Strunz-mindat GroupingHide

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8.DC.CésarferreiraiteFe2+ Fe3+2(AsO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.FerrivauxiteFe3+Al2(PO4)2(OH)3 · 5H2OTric. 1 : P1
8.DC.IanbruceiteZn2(AsO4)(OH) · 3H2OMon. 2/m : P21/b
8.DC.05NissoniteCu2Mg2(PO4)2(OH)2 · 5H2OMon. 2/m : B2/b
8.DC.07EuchroiteCu2(AsO4)(OH) · 3H2OOrth. 222 : P212121
8.DC.10LegranditeZn2(AsO4)(OH) · H2OMon. 2/m : P21/b
8.DC.12StrashimiriteCu8(AsO4)4(OH)4 · 5H2OMon.
8.DC.15EarlshannoniteMn2+Fe3+2(PO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15KunatiteCuFe3+2(PO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15'UM2006-27-PO:FeHZn'ZnFe3+2(PO4)2(OH)2 · 4H2OMon.
8.DC.15'UKI-2006-(PO:AlCuFeH)'Fe2+Al3+2(PO4)2(OH)2 · 4H2O
8.DC.15CobaltarthuriteCoFe3+2(AsO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15ArthuriteCuFe3+2(AsO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15OjuelaiteZnFe3+2(AsO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15WhitmoreiteFe2+Fe3+2(PO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15BendadaiteFe2+Fe3+2(AsO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.17KleemaniteZnAl2(PO4)2(OH)2 · 3H2OMon.
8.DC.20MagnesiobermaniteMgMn3+2(PO4)2(OH)2 · 4H2OMon. 2 : P21
8.DC.20BermaniteMn2+Mn3+2(PO4)2(OH)2 · 4H2OMon. 2/m : P2/b
8.DC.20CoralloiteMn2+Mn3+2(AsO4)2(OH)2 · 4H2OTric. 1 : P1
8.DC.22KovdorskiteMg2(PO4)(OH) · 3H2OMon. 2/m : P21/b
8.DC.25ZincostrunziteZnFe3+2(PO4)2(OH)2 · 6.5H2OTric. 1 : P1
8.DC.25MetavauxiteFe2+Al2(PO4)2(OH)2 · 8H2OMon. 2/m : P21/b
8.DC.25MetavivianiteFe2+Fe3+2(PO4)2(OH)2 · 6H2OTric. 1 : P1
8.DC.25FerristrunziteFe3+Fe3+2(PO4)2(OH)3 · 5H2OTric.
8.DC.25StrunziteMn2+Fe3+2(PO4)2(OH)2 · 6H2OTric. 1 : P1
8.DC.25FerrostrunziteFe2+Fe3+2(PO4)2(OH)2 · 6H2OTric.
8.DC.27BerauniteFe3+6(PO4)4O(OH)4 · 6H2OMon. m : Bb
8.DC.27TvrdýiteFe2+Fe3+2Al3(PO4)4(OH)5(H2O)4 · 2H2OMon. 2/m : B2/b
8.DC.27ZincoberauniteZnFe3+5(PO4)4(OH)5 · 6H2OMon. 2/m : B2/b
8.DC.30MaghrebiteMgAl2(AsO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30FerrolaueiteFe2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30UshkoviteMgFe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30LaueiteMn2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30ParavauxiteFe2+Al2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30SigloiteFe3+Al2(PO4)2(OH)3 · 7H2OTric. 1 : P1
8.DC.30NordgauiteMnAl2(PO4)2(F,OH)2 · 5H2OTric. 1 : P1
8.DC.30KummeriteMn2+Fe3+Al(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30MangangordoniteMn2+Al2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30StewartiteMn2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30GordoniteMgAl2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30Kastningite(Mn2+,Fe2+,Mg)Al2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30PseudolaueiteMn2+Fe3+2(PO4)2(OH)2 · 8H2OMon. 2/m : P21/b
8.DC.32KamarizaiteFe3+3(AsO4)2(OH)3 · 3H2OTric. 1 : P1
8.DC.32TinticiteFe3+3(PO4)2(OH)3 · 3H2OTric. 1 : P1
8.DC.35VauxiteFe2+Al2(PO4)2(OH)2 · 6H2OTric. 1 : P1
8.DC.37VantasseliteAl4(PO4)3(OH)3 · 9H2OOrth.
8.DC.40CacoxeniteFe3+24AlO6(PO4)17(OH)12 · 75H2OHex. 6/m : P63/m
8.DC.45Souzalite(Mg,Fe2+)3(Al,Fe3+)4(PO4)4(OH)6 · 2H2OTric. 1
8.DC.45Gormanite(Fe2+,Mg)3(Al,Fe3+)4(PO4)4(OH)6 · 2H2OTric.
8.DC.47KingiteAl3(PO4)2F2(OH) · 7H2OTric.
8.DC.50AllanpringiteFe3+3(PO4)2(OH)3 · 5H2OMon. 2/m : P21/m
8.DC.50FluorwavelliteAl3(PO4)2(OH)2F · 5H2OOrth. mmm(2/m2/m2/m)
8.DC.50WavelliteAl3(PO4)2(OH)3 · 5H2OOrth. mmm(2/m2/m2/m)
8.DC.52KribergiteAl5(PO4)3(SO4)(OH)4 · 4H2OTric. 1 : P1
8.DC.55MapimiteZn2Fe3+3(AsO4)3(OH)4 · 10H2OMon. m : Bm
8.DC.57OgdensburgiteCa2Fe3+4(Zn,Mn2+)(AsO4)4(OH)6 · 6H2OOrth. mmm(2/m2/m2/m) : Cmmm
8.DC.60CloncurryiteCu0.5(VO)0.5Al2(PO4)2F2 · 5H2OMon. 2/m : P21/b
8.DC.60Nevadaite(Cu2+,Al,V3+)6Al8(PO4)8F8(OH)2 · 22H2OOrth. mmm(2/m2/m2/m)
8.DC.62KenngottiteMn2+3Fe3+4(PO4)4(OH)6(H2O)2 Mon. 2/m : P2/b
8.DC.67MolinelloiteCu(H2O)(OH)V4+O(V5+O4)Tric. 1 : P1
8.DC.70WhitecapsiteH16Fe2+5Fe3+14Sb3+6(AsO4)18O16 · 120H2OHex. 6/m : P63/m
8.DC.75HeimitePbCu2(AsO4)(OH)3 · 2H2OMon. 2/m
8.DC.80LedneviteCu[PO3(OH)] · H2OMon. 2/m : P21/b

Other InformationHide

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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 KayrobertsoniteHide

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mindat.org URL:
https://www.mindat.org/min-46697.html
Please feel free to link to this page.

References for KayrobertsoniteHide

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Localities for KayrobertsoniteHide

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Showing 4 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the 👁 Image
symbol to view information about a locality. The 👁 Image
symbol next to localities in the list can be used to jump to that position on the map.

Locality ListHide

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👁 Image
- This locality has map coordinates listed. 👁 Image
- This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. 👁 Image
- Good crystals or important locality for species. 👁 Image
- 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.
Germany
  • Bavaria
    • Lower Bavaria
      • Regen District
        • Zwiesel
          • Rabenstein
Grey et al. (2026)
    • Upper Palatinate
      • Neustadt an der Waldnaab District
        • Waidhaus
          • Hagendorf
Hålenius et al. (2015) +1 other reference
EDS Jason B. Smith
USA (TL)
  • North Carolina
    • Cleveland County
      • Kings Mountain
Hålenius et al. (2015) +2 other references
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