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Jahnsite-(CaMgMg)

Valid as an unnamed mineral
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01661380017271924193753.jpg
Richard H. Jahns
Formula:
{Ca}{Mg}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2O
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.
Jahnsite Group.


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Unique IdentifiersHide

Mindat ID:
35968
Long-form identifier:
mindat:1:1:35968:3

Similar NamesHide

JahnsiteA synonym of Jahnsite SubgroupXM1M22M32(H2O)8(OH)2(PO4)4
Jahnsite-(CaFeFe)Valid as an unnamed mineral{Ca}{Fe2+}{Fe22+}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(CaFeMg)A valid IMA mineral species{Ca}{Fe2+}{Mg2}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(CaMnFe)A valid IMA mineral species{Ca}{Mn2+}{Fe22+}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(CaMnMg)A valid IMA mineral species{Ca}{Mn2+}{(Mg,Fe2+)2}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(CaMnMn)A valid IMA mineral species{Ca}{Mn2+}{Mn22+}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(CaMnZn)A valid IMA mineral species{Ca}{Mn2+}{Zn2}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(MnMnFe)A valid IMA mineral species{Mn2+}{Mn2+}{Fe22+}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(MnMnMg)A valid IMA mineral species{Mn2+}{Mn2+}{Mg2}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(MnMnMn)A valid IMA mineral species{Mn2+}{Mn2+}{Mn22+}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(MnMnZn)A valid IMA mineral species{Mn2+}{Mn2+}{Zn2}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(NaFeMg)A valid IMA mineral species{Na}{Fe3+}{Mg2}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(NaMnMg)A valid IMA mineral species{(Na,Ca)}{(Mn2+,Fe3+)}{(Mg,Fe3+)2}{Fe23+}(PO4)4(OH)2 · 8H2O
Jahnsite-(NaMnMn)A valid IMA mineral species{Na}{Mn2+}{(Mn2+,Fe3+)2}{Fe23+}(PO4)4(OH)2 · 8H2O
JanositeA synonym of CopiapiteFe2+Fe43+(SO4)6(OH)2 · 20H2O
JonesiteA valid IMA mineral speciesBa4(K,Na)2Ti4Al2(Si3O9)2(SiO4)4O2 · 6H2O

Classification of Jahnsite-(CaMgMg)Hide

04249070017684452162373.jpg
The jahnsite structure archetype

The structure archetype of jahnsite group minerals, which includes the jahnsite and whiteite subgroups.

IMA Classification of Jahnsite-(CaMgMg)Hide

IMA status notes:
Unnamed (probably valid)
Approval history:
Unnamed, but probably valid.
Strunz-mindat (2026):
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
Dana 8th ed.:
42.11.2.9

42 : HYDRATED PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
11 : (AB)3(XO4)2Zq·xH2O

Chemistry of Jahnsite-(CaMgMg)Hide

Mindat Formula:
{Ca}{Mg}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2O
Element Weights:
Element% weight
O53.147 %
P15.829 %
Fe14.270 %
Mg9.316 %
Ca5.120 %
H2.318 %

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

Relationship of Jahnsite-(CaMgMg) 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-(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-(MnMnMg){Mn2+}{Mn2+}{Mg2}{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

Associations Based on Photo Data:
3 photos of Jahnsite-(CaMgMg) associated with Jahnsite-(NaFeMg){Na}{Fe3+}{Mg2}{Fe3+2}(PO4)4(OH)2 · 8H2O
3 photos of Jahnsite-(CaMgMg) associated with Jahnsite-(NaMnMg){(Na,Ca)}{(Mn2+,Fe3+)}{(Mg,Fe3+)2}{Fe3+2}(PO4)4(OH)2 · 8H2O
2 photos of Jahnsite-(CaMgMg) associated with Jahnsite-(CaMnMg){Ca}{Mn2+}{(Mg,Fe2+)2}{Fe3+2}(PO4)4(OH)2 · 8H2O

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-(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.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/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

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-(CaMgMg)Hide

References for Jahnsite-(CaMgMg)Hide

Localities for Jahnsite-(CaMgMg)Hide

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.
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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.
Chile
 
  • Antofagasta
    • Antofagasta Province
      • Mejillones
        • Mejillones peninsula
SEM-EDS by Joy Desor and Gerhard Möhn +1 other reference
USA
 
  • South Dakota
    • Custer County
      • Custer Mining District
        • Fourmile
Am.Min. 93 (2008)
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