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Kastningite

A valid IMA mineral species
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04329670017271928799840.jpg
Kastningite

Foote Lithium Co. Mine, Kings Mountain, Cleveland County, North Carolina, USA
02119360017552157632976.jpg
Kastningite, etc.

Foote Lithium Co. Mine, Kings Mountain, Cleveland County, North Carolina, USA
03800960017552157643488.jpg
Kastningite

Silbergrube, Waidhaus, Neustadt an der Waldnaab District, Upper Palatinate, Bavaria, Germany
04329670017271928799840.jpg
Kastningite

Foote Lithium Co. Mine, Kings Mountain, Cleveland County, North Carolina, USA
09041750017363088376236.jpg
Kastningite, etc.

Foote Lithium Co. Mine, Kings Mountain, Cleveland County, North Carolina, USA
01844770017363042073925.jpg
Kastningite

Silbergrube, Waidhaus, Neustadt an der Waldnaab District, Upper Palatinate, Bavaria, Germany
04329670017271928799840.jpg
Kastningite

Foote Lithium Co. Mine, Kings Mountain, Cleveland County, North Carolina, USA
02087270017552156372143.jpg
Kastningite, etc.

Foote Lithium Co. Mine, Kings Mountain, Cleveland County, North Carolina, USA
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About KastningiteHide

09395030017271928928387.jpg
Jürgen Kastning
Formula:
(Mn2+,Fe2+,Mg)Al2(PO4)2(OH)2 · 8H2O
Colour:
Generally colorless, may be white
Lustre:
Vitreous
Hardness:
1 - 2
Specific Gravity:
2.35
Crystal System:
Triclinic
Name:
Named in 1999 by Jochen Schlüter, Karl-Heinz Klaska, Karen Friese, and Gunadi Adiwidjaja after Jürgen Kastning (1932 - 5 January 2017), from Reinbeck near Hamburg, Germany, mineral collector and mineral dealer specializing in phosphate minerals, who discovered the mineral.
Dimorph of:
Mangangordonite
Isostructural with:
Stewartite
DANGER: Kastningite easily dehydrates and decomposes near hot illumination sources. The kastningite crystals become chalky and are probably no longer crystalline. Lighting units should be very far away from specimens (> 20 cm) when they are being photographed. LED lights can be hot enough to dehydrate this species. (See also posting by Jason B. Smith in https://www.mindat.org/mesg-640023.html).


Unique IdentifiersHide

Mindat ID:
7129
Long-form identifier:
mindat:1:1:7129:7

Classification of KastningiteHide

05521570017685316117551.jpg
Laueite structure archetype

In kastningite, the M1 site is occupied by Mn2+ and the M2 and M3 sites are occupied by Al3+. The X site is a phosphate group.

IMA Classification of KastningiteHide

IMA status:
Approved
IMA Formula:
Mn2+Al2(PO4)2(OH)2·8H2O
Approval year:
1997
First published:
1999
Strunz-mindat (2026):
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

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

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

Physical Properties of KastningiteHide

Lustre:
Vitreous
Transparency:
Transparent, Translucent
Comment:
May be etched with reduced luster.
Colour:
Generally colorless, may be white
Streak:
White
Hardness:
1 - 2 on Mohs scale
Tenacity:
Brittle
Density:
2.35 g/cm3 (Measured)    2.379 g/cm3 (Calculated)

Optical Data of KastningiteHide

Type:
Biaxial (-)
RI values:
nα = 1.5665 nβ = 1.574 nγ = 1.5815
2V:
Measured: 94.7° , Calculated: 90.6°
Birefringence:
0.015
Max. Birefringence:
δ = 0.015
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 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:
r > v strong
Pleochroism:
Non-pleochroic

Chemistry of KastningiteHide

Mindat Formula:
(Mn2+,Fe2+,Mg)Al2(PO4)2(OH)2 · 8H2O
Element Weights:
Element% weight
O60.378 %
P12.987 %
Mn11.518 %
Al11.314 %
H3.804 %

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

Crystallography of KastningiteHide

Crystal System:
Triclinic
Class (H-M):
1 - Pinacoidal
Space Group:
P1
Setting:
P1
Cell Parameters:
a = 7.010 Å, b = 10.205 Å, c = 10.504 Å
α = 71.82°, β = 89.62°, γ = 69.90°
Ratio:
a:b:c = 0.687 : 1 : 1.029
Unit Cell V:
666.16 ų (Calculated from Unit Cell)
Z:
2
Morphology:
Commonly found in euhedral crystals. Usually thin bladed with acutely sloping terminations. Tabular on [001], showing {001}, {111}, {111}, {100}. Length of an individual crystals rarely reaches 1 mm in size.

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0011083KastningiteAdiwidjaja G, Friese K, Klaska K H, Schluter J (1999) The crystal structure of kastningite (Mn,Fe,Mg)(H2O)4[Al2(OH)2(H2O)2(PO4)2]*2H2O - a new hydroxyl aquated orthophosphate hydrate mineral Zeitschrift fur Kristallographie 214 465-4681999Waidhaus, Bavaria, Germany0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
9.917 Å(100)
6.541 Å(36)
4.957 Å(50)
3.312 Å(23)
3.095 Å(28)
3.001 Å(30)
1.653 Å(25)

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 4b: Highly evolved igneous rocks>3.0
34 : Complex granite pegmatites
Stage 7: Great Oxidation Event<2.4
47a : [Near-surface hydration of prior minerals]
47c : [Carbonates, phosphates, borates, nitrates]
47e : [Vanadates, chromates, manganates]
Geological Setting:
Granite pegmatite.

Type Occurrence of KastningiteHide

Type Locality:
ⓘ Silbergrube, Waidhaus, Neustadt an der Waldnaab District, Upper Palatinate, Bavaria, Germany
General Appearance of Type Material:
Sprays of thin, tabular crystals, up to 2 mm long.
Place of Conservation of Type Material:
Mineralogical Museum, University of Hamburg, Hamburg, Germany.
Geological Setting of Type Material:
Granite pegmatite.
Associated Minerals at Type Locality:
ParavauxiteVariscite

Synonyms of KastningiteHide

Other Language Names for KastningiteHide

Relationship of Kastningite to other SpeciesHide

Member of:
Laueite Group > Laueite Supergroup
Other Members of Laueite Group:
CuretoniteBa(Al,Ti)(PO4)(OH,O)FMon. 2/m
FerrolaueiteFe2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
GordoniteMgAl2(PO4)2(OH)2 · 8H2OTric. 1 : P1
KummeriteMn2+Fe3+Al(PO4)2(OH)2 · 8H2OTric. 1 : P1
LaueiteMn2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
MangangordoniteMn2+Al2(PO4)2(OH)2 · 8H2OTric. 1 : P1
ParavauxiteFe2+Al2(PO4)2(OH)2 · 8H2OTric. 1 : P1
SigloiteFe3+Al2(PO4)2(OH)3 · 7H2OTric. 1 : P1
StewartiteMn2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
UshkoviteMgFe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1

Common AssociatesHide

Associations Based on Photo Data:
4 photos of Kastningite associated with MangangordoniteMn2+Al2(PO4)2(OH)2 · 8H2O
4 photos of Kastningite associated with StrengiteFePO4 · 2H2O
3 photos of Kastningite associated with CacoxeniteFe3+24AlO6(PO4)17(OH)12 · 75H2O
3 photos of Kastningite associated with Kayrobertsonite[MnAl2(PO4)2(OH)2(H2O)4] · 2H2O
3 photos of Kastningite associated with EarlshannoniteMn2+Fe3+2(PO4)2(OH)2 · 4H2O
3 photos of Kastningite associated with Rittmannite{(Mn2+,Ca)}{Mn2+}{(Fe2+,Mn2+,Mg)2}{(Al,Fe3+)2}(PO4)4(OH)2 · 8H2O
2 photos of Kastningite associated with AlbiteNa(AlSi3O8)
1 photo of Kastningite associated with FluorapatiteCa5(PO4)3F
1 photo of Kastningite associated with EosphoriteMn2+Al(PO4)(OH)2 · H2O
1 photo of Kastningite associated with StrunziteMn2+Fe3+2(PO4)2(OH)2 · 6H2O

Related Minerals - Strunz-mindat GroupingHide

8.DC.FerroberauniteFe2+Fe3+5(PO4)4(OH)5 · 6H2OMon. 2/m : B2/b
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.30Kayrobertsonite[MnAl2(PO4)2(OH)2(H2O)4] · 2H2OTric. 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.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.45SouzaliteMg3Al4(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

Fluorescence of KastningiteHide

In UV light:
Not Fluorescent in UV

Other InformationHide

Special Storage/
Display Requirements:
Kastningite easily dehydrates and decomposes near hot illumination sources. The kastnigite crystals become chalky and are probably no longer crystalline. Lighting units should be very far away from specimens (> 20 cm) when they are being photographed. LED lights can be hot enough to dehydrate this species.
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 KastningiteHide

References for KastningiteHide

Localities for KastningiteHide

Showing 11 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.
Brazil
 
  • Minas Gerais
    • Galiléia
      • Sapucaia do Norte
Sergio Varvello collection
Europe
 
Berbain et al. (2012)
France
 
  • Occitanie
    • Pyrénées-Orientales
      • Céret
        • Collioure
Berbain et al. (2012)
Germany
 
  • Bavaria
    • Upper Palatinate
      • Neustadt an der Waldnaab District
        • Waidhaus
          • Hagendorf
web.archive.org (2001) +1 other reference
Schlüter et al. (1999) +1 other reference
Portugal
 
  • Guarda
    • Sabugal
      • Bendada
Alves (n.d.)
Pedro Alves collection - pXRD analyzed
USA
 
  • Maine
    • Oxford County
      • Greenwood
        • Uncle Tom Mountain
Jason B. Smith. +1 other reference
      • Newry
King (n.d.)
  • North Carolina
    • Cleveland County
      • Kings Mountain
confirmed by EDS/XRD +1 other reference
    • Gaston County
site indentification by comparsion to ...
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