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Jahnsite-(MnMnMg)

A valid IMA mineral species
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00863300017271951763420.jpg
Jahnsite-(MnMnMg)

Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
09832830017271951778136.jpg
Jahnsite-(MnMnMg)

Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
03832030017271951808820.jpg
Jahnsite-(MnMnMg)

Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
00863300017271951763420.jpg
Jahnsite-(MnMnMg)

Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
09832830017271951778136.jpg
Jahnsite-(MnMnMg)

Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
03832030017271951808820.jpg
Jahnsite-(MnMnMg)

Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
00863300017271951763420.jpg
Jahnsite-(MnMnMg)

Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
09832830017271951778136.jpg
Jahnsite-(MnMnMg)

Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
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About Jahnsite-(MnMnMg)Hide

01661380017271924193753.jpg
Richard H. Jahns
Formula:
{Mn2+}{Mn2+}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2O
Colour:
Yellow to honey-colored or greenish-yellow
Lustre:
Vitreous
Hardness:
4
Specific Gravity:
2.625 (Calculated)
Crystal System:
Monoclinic
Name:
The root name is in honor of Richard Henry Jahns (March 10, 1915 Los Angeles, California, USA - December 31, 1983 Palo Alto, California, USA), mineralogist and pegmatite expert, Stanford University, Palo Alto, California, USA. The suffix indicates metal site occupancies.
This page provides mineralogical data about Jahnsite-(MnMnMg).


Unique IdentifiersHide

Mindat ID:
43541
Long-form identifier:
mindat:1:1:43541:5

IMA Classification of Jahnsite-(MnMnMg)Hide

Classification of Jahnsite-(MnMnMg)Hide

Strunz-mindat (2025):
8.DH.15

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

Mineral SymbolsHide

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

Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.

SymbolSourceReference
Jah-MnMnMgIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
JhnThe Canadian Mineralogist (2019)The Canadian Mineralogist (2019) The Canadian Mineralogist list of symbols for rock- and ore-forming minerals (December 30, 2019). download

Physical Properties of Jahnsite-(MnMnMg)Hide

Lustre:
Vitreous
Transparency:
Transparent
Colour:
Yellow to honey-colored or greenish-yellow
Streak:
Very pale yellow
Hardness:
4 on Mohs scale
Tenacity:
Brittle
Cleavage:
Distinct/Good
{001}
Fracture:
Irregular/Uneven
Density:
2.625 g/cm3 (Calculated)

Optical Data of Jahnsite-(MnMnMg)Hide

Type:
Biaxial (-)
RI values:
nα = 1.616 nβ = 1.619 nγ = 1.656
2V:
Calculated: 74°
Max. Birefringence:
δ = 0.040
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

Chemistry of Jahnsite-(MnMnMg)Hide

Mindat Formula:
{Mn2+}{Mn2+}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2O
Element Weights:
Element% weight
O50.228 %
P14.960 %
Fe13.486 %
Mn13.267 %
Mg5.869 %
H2.191 %

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

Crystallography of Jahnsite-(MnMnMg)Hide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P2/b
Setting:
P2/a
Cell Parameters:
a = 15.177(2) Å, b = 7.176(1) Å, c = 10.006(3) Å
β = 111.01(2)°
Ratio:
a:b:c = 2.115 : 1 : 1.394
Unit Cell V:
1,017.31 ų (Calculated from Unit Cell)
Z:
2

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
9.28 Å(100)
4.945 Å(39)
4.627 Å(20)
3.521 Å(43)
2.988 Å(52)
2.842 Å(81)
1.958 Å(27)
1.581 Å(27)

Geological EnvironmentHide

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

Type Occurrence of Jahnsite-(MnMnMg)Hide

Type Locality:
ⓘ Sapucaia mine, Sapucaia do Norte, Galiléia, Minas Gerais, Brazil
General Appearance of Type Material:
It forms prisms weakly elongated along a, flattened on [010], and twinned by reflection on {001} up to 200 μm in length.
Place of Conservation of Type Material:
mineralogical collections of the Laboratoire de Minéralogie, University of Liege, Bât. B18, Sart Tilman, B-4000 Liège, Belgium, catalogue no. 21140
Associated Minerals at Type Locality:
FrondeliteLeucophosphiteMangangordonite
Reference:
Vignola, Pietro, Hatert, Frédéric, Baijot, Maxime, Rotiroti, Nicola, Risplendente, Andrea, Varvello, Sergio (2019) Jahnsite-(MnMnMg), Mn2+Mn2+Mg2+2Fe3+2(PO4)4(OH)2·8H2O, a new phosphate mineral species from Sapucaia pegmatite, Sapucaia Do Norte, Galiléia, Minas Gerais, Brazil. The Canadian Mineralogist, 57 (3) 363-370 doi:10.3749/canmin.1800078

Other Language Names for Jahnsite-(MnMnMg)Hide

Relationship of Jahnsite-(MnMnMg) to other SpeciesHide

Member of:
Jahnsite Subgroup > Jahnsite Group
Other Members of Jahnsite Subgroup:
Jahnsite-(CaFeFe){Ca}{Fe2+}{Fe2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon.
Jahnsite-(CaFeMg){Ca}{Fe2+}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(CaMgMg){Ca}{Mg}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2O
Jahnsite-(CaMnFe){Ca}{Mn2+}{Fe2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(CaMnMg){Ca}{Mn2+}{(Mg,Fe2+)2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(CaMnMn){Ca}{Mn2+}{Mn2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(CaMnZn){Ca}{Mn2+}{Zn2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(MnMnFe){Mn2+}{Mn2+}{Fe2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(MnMnMn){Mn2+}{Mn2+}{Mn2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P21/b
Jahnsite-(MnMnZn){Mn2+}{Mn2+}{Zn2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(NaFeMg){Na}{Fe3+}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(NaMnMg){(Na,Ca)}{(Mn2+,Fe3+)}{(Mg,Fe3+)2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
Jahnsite-(NaMnMn){Na}{Mn2+}{(Mn2+,Fe3+)2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
KeckiteCaMn2+(Fe3+Mn2+)Fe3+2(PO4)4(OH)3 · 7H2OMon. 2/m : P2/b

Common AssociatesHide

Associated Minerals Based on Photo Data:
1 photo of Jahnsite-(MnMnMg) associated with Meurigite-KKFe3+8(PO4)6(OH)7 · 6.5H2O

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.FerroberauniteFe2+Fe3+5(PO4)4(OH)5 · 6H2OMon. 2/m : B2/b
8.DH.RegeriteKFe6(PO4)4(OH)7(H2O)6 · 4H2OMon. 2/m : P21/b
8.DH.Ammoniotinsleyite(NH4)Al2(PO4)2(OH) · 2H2OMon. 2/m : P21/m
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/m 2/m 2/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-(MnMnFe){Mn2+}{Mn2+}{Fe2+2}{Fe3+2}(PO4)4(OH)2 · 8H2OMon. 2/m : P2/b
8.DH.15Jahnsite-(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.15Jahnsite-(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.15Kaluginite(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/m 2/m 2/m) : Pcca
8.DH.20Lun'okite(Mn,Ca)(Mg,Fe,Mn)Al(PO4)2OH · 4H2OOrth. mmm (2/m 2/m 2/m) : Pbca
8.DH.20Manganosegelerite(Mn2+,Ca)(Mn2+,Fe2+,Mg)Fe3+(PO4)2(OH) · 4H2OOrth. mmm (2/m 2/m 2/m) : Pbca
8.DH.20WilhelmvierlingiteCaMnFe3+(PO4)2(OH) · 2H2OOrth. mmm (2/m 2/m 2/m) : Pbca
8.DH.20JuonniiteCaMgSc(PO4)2(OH) · 4H2OOrth. mmm (2/m 2/m 2/m) : Pbca
8.DH.20OveriteCaMgAl(PO4)2(OH) · 4H2OOrth. mmm (2/m 2/m 2/m) : Pbca
8.DH.25CalcioferriteCa2Fe3+2(PO4)3(OH) · 7H2OMon. 2/m : B2/b
8.DH.25ZodaciteCa4Mn2+Fe3+4(PO4)6(OH)4 · 12H2OMon.
8.DH.25FanfaniiteCa4MnAl4(PO4)6(OH)4 · 12H2OMon. 2/m : B2/b
8.DH.25KingsmountiteCa3MnFeAl4(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.30RobertsiteCa2Mn3+3(PO4)3O2 · 3H2OMon. m : Bb
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/m 2/m 2/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/m 2/m 2/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/m 2/m 2/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/m 2/m 2/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/m 2/m 2/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 Jahnsite-(MnMnMg)Hide

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 Jahnsite-(MnMnMg)Hide

References for Jahnsite-(MnMnMg)Hide

Localities for Jahnsite-(MnMnMg)Hide

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.

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
    • Conselheiro Pena
      • Barra do Cuieté
Sergio Varvello collection
    • Galiléia
      • Sapucaia do Norte
Baijot et al. (2012)
Quick NavTopAbout Jahnsite-(MnMnMg)Unique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionGeological EnvironmentType Occurrence Other LanguagesRelationshipsCommon AssociatesStrunz-MindatFluorescence Other InformationInternet Links References Localities Locality List
 
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