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Jahnsite-(CaMnFe)

Big Photo

Tip Top Mine, Fourmile, Custer District, Custer Co., South Dakota, USA
© Saul Krotki 2004

Show Jahnsite-(CaMnFe) Photos (10)
Formula:
CaMn
2+
 
Fe
2+
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
System:MonoclinicColour:Brown, Purplish brown, ...
Hardness:4
Name:Named for Richard H. Jahns (1915-1983), mineralogist and pegmatite expert, Stanford University, Palo Alto, California, USA
This page provides mineralogical data about Jahnsite-(CaMnFe).

Classification of Jahnsite-(CaMnFe)

IMA status:Approved
Strunz 8th edition ID:7/D.29-60
Strunz 9th edition ID:8.DH.15
Nickel-Strunz 10th (pending) edition ID: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 edition ID:42.11.2.2

42 : HYDRATED PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
11 : (AB)3(XO4)2Zq·xH2O
Hey's CIM Ref.:19.12.41

19 : Phosphates
12 : Phosphates of Mn
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Type Occurrence of Jahnsite-(CaMnFe)

Type Locality:Fletcher Quarry, Groton, Grafton Co., New Hampshire, USA

Physical Properties of Jahnsite-(CaMnFe)

Lustre:Adamantine, Vitreous
Diaphaneity (Transparency):Transparent, Translucent
Colour:Brown, Purplish brown, Yellow, Yellow orange
Streak:White
Hardness (Mohs):4
Tenacity:Brittle
Cleavage:Distinct/Good
Good on the {001}
Density (measured):2.86 g/cm3
Density (calculated):2.95 g/cm3

Crystallography of Jahnsite-(CaMnFe)

Crystal System:Monoclinic
Class (H-M):2/m - Prismatic
Cell Parameters:a = 15.01Å, b = 7.15Å, c = 9.87Å
β = 111.23°
Ratio:a:b:c = 2.099 : 1 : 1.38
Unit Cell Volume:V 987.38 ų
Z:2

Chemical Properties of Jahnsite-(CaMnFe)

Formula:
CaMn
2+
 
Fe
2+
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
Essential elements:Ca, Fe, H, Mn, O, P
All elements listed in formula:Ca, Fe, H, Mn, O, P

Relationship of Jahnsite-(CaMnFe) to other Species

Related Minerals - Nickel-Strunz Grouping):
8.DH.05Minyulite
KAl
 
2
[(OH,F)|(PO
 
4
)
 
2
] · 4H
 
2
O
8.DH.10Leucophosphite
KFe
3+
2
[OH|(PO
 
4
)
 
2
] · 2H
 
2
O
8.DH.10Spheniscidite
(NH
 
4
,K)(Fe
3+
 
,Al)
 
2
[OH|(PO
 
4
)
 
2
] · 2H
 
2
O
8.DH.10Tinsleyite
KAl
 
2
[OH|(PO
 
4
)
 
2
] · 2H
 
2
O
8.DH.15Jahnsite-(CaMnMg)
CaMn
2+
 
(Mg,Fe
2+
 
)
 
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.15Jahnsite-(CaMnMn)
CaMn
2+
 
Mn
2+
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.15Keckite
(Ca,Mg)(Mn
2+
 
,Zn)
 
2
Fe
3+
3
(PO
 
4
)
 
4
(OH)
 
3
 · 2H
 
2
O
8.DH.15Rittmannite
(Mn
2+
 
,Ca)Mn
2+
 
(Fe
2+
 
,Mn
2+
 
,Mg)
 
2
(Al,Fe
3+
 
)
 
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.15Whiteite-(CaFeMg)
Ca(Fe
2+
 
,Mn
2+
 
)Mg
 
2
Al
 
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.15Whiteite-(CaMnMg)
CaMn
2+
 
Mg
 
2
Al
 
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.15Whiteite-(MnFeMg)
(Mn
2+
 
,Ca)(Fe
2+
 
,Mn
2+
 
)Mg
 
2
Al
 
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.15Jahnsite-(MnMnMn)
Mn
2+
 
Mn
2+
 
Mn
2+
2
Fe
3+
2
(PO
 
4
)
 
4
](OH)
 
2
 · 8H
 
2
O
8.DH.15Kaluginite
(Mn
2+
 
,Ca)MgFe
3+
 
[OH|(PO
 
4
)
 
2
] · 4H
 
2
O
8.DH.15Jahnsite-(CaFeFe)
CaFeFe
 
2
Fe
 
2
(PO
 
4
)
 
4
(OH)
 
2
·8H
 
2
O
8.DH.15Jahnsite-(NaFeMg)
NaFe
3+
 
Mg
 
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.15Jahnsite-(NaMnMg)
NaMnMg
 
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.15Jahnsite-(CaMgMg)
CaMgMg
 
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.20Manganosegelerite
(Mn
2+
 
,Ca)(Mn
2+
 
,Fe
2+
 
,Mg)Fe
3+
 
(PO
 
4
)
 
2
(OH)
 
2
 · 4H
 
2
O
8.DH.20Overite
CaMgAl[OH|(PO
 
4
)
 
2
] · 4H
 
2
O
8.DH.20Segelerite
Ca
 
2
 Mg
 
2
 Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
8.DH.20Wilhelmvierlingite
CaMnFe
3+
 
[OH|(PO
 
4
)
 
2
] · 2H
 
2
O
8.DH.20Juonniite
CaMgSc(PO
 
4
)
 
2
(OH)·4H
 
2
O
8.DH.25Calcioferrite
Ca
 
2
Fe
3+
2
[OH|(PO
 
4
)
 
3
] · 7H
 
2
O
8.DH.25Kingsmountite
Ca
 
4
(Fe
2+
 
,Mn
2+
 
)Al
 
4
[(OH)
 
2
|(PO
 
4
)
 
3
]
 
2
 · 12H
 
2
O
8.DH.25Montgomeryite
Ca
 
4
MgAl
 
4
[(OH)
 
2
|(PO
 
4
)
 
3
]
 
2
 · 12H
 
2
O
8.DH.25Zodacite
Ca
 
4
Mn
2+
 
Fe
3+
4
[(OH)
 
2
|(PO
 
4
)
 
3
]
 
2
 · 12H
 
2
O
8.DH.30Arseniosiderite
Ca
 
2
Fe
3+
3
[O
 
2
|(AsO
 
4
)
 
3
] · 3H
 
2
O
8.DH.30Kolfanite
Ca
 
2
Fe
3+
2
[O
 
2
|(AsO
 
4
)
 
3
] · 2H
 
2
O
8.DH.30Mitridatite
Ca
 
2
Fe
3+
3
[O
 
2
|(PO
 
4
)
 
3
] · 3H
 
2
O
8.DH.30Pararobertsite
Ca
 
2
Mn
3+
3
[O
 
2
|(PO
 
4
)
 
3
] · 3H
 
2
O
8.DH.30Robertsite
Ca
 
3
Mn
3+
4
[(OH)
 
3
|(PO
 
4
)
 
2
]
 
2
 · 3H
 
2
O
8.DH.30Sailaufite
Ca
 
2
Mn
3+
3
[O|CO
 
3
|(AsO
 
4
)
 
2
] · 3H
 
2
O
8.DH.35Mantienneite
KMg
 
2
Al
 
2
Ti[(OH)
 
3
|(PO
 
4
)
 
4
] · 15H
 
2
O
8.DH.35Paulkerrite
K(Mg,Mn
2+
 
)
 
2
(Fe
3+
 
,Al,Ti,Mg)
 
2
Ti(PO
 
4
)
 
4
(OH)
 
3
 · 15H
 
2
O
8.DH.35Benyacarite
(H
 
2
O,K)
 
2
(Mn
2+
 
,Fe
2+
 
)
 
2
(Fe
3+
 
,Ti)
 
2
Ti[(O,F)
 
2
|(PO
 
4
)
 
4
] · 14H
 
2
O
8.DH.40Xanthoxenite
Ca
 
4
Fe
3+
2
[OH|(PO
 
4
)
 
2
]
 
2
 · 3H
 
2
O
8.DH.45Mahnertite
NaCu
 
3
(AsO
 
4
)
 
2
Cl · 5H
 
2
O
8.DH.50Andyrobertsite
KCdCu
 
5
[H
 
2
AsO4|(AsO
 
4
)
 
4
] · 2H
 
2
O
8.DH.50Calcioandyrobertsite
KCaCu
 
5
[H
 
2
AsO
 
4
|(AsO
 
4
)
 
4
] · 2H
 
2
O
8.DH.55Englishite
K
 
3
Na
 
2
Ca
 
10
Al
 
15
[OH|(PO
 
4
)
 
3
]
 
7
 · 26H
 
2
O
8.DH.60Bouazzerite
Bi
 
6
(Mg,Co)
 
11
Fe
3+
14
(AsO
 
4
)
 
18
O
 
12
(OH)
 
4
(H
 
2
O)
 
86
Related Minerals - Hey's Index Grouping:
19.12.1Metaswitzerite
Mn
 
3
(PO
 
4
)
 
2
·4H
 
2
O
19.12.2Bermanite
Mn
2+
 
Mn
3+
2
[OH|PO
 
4
]
 
2
 · 4H
 
2
O
19.12.3Natrophilite
NaMn
2+
 
[PO
 
4
]
19.12.4Sidorenkite
Na
 
3
Mn
2+
 
[PO
 
4
|CO
 
3
]
19.12.5Niahite
(NH
 
4
)(Mn
2+
 
,Mg)[PO
 
4
] · H
 
2
O
19.12.6Robertsite
Ca
 
3
Mn
3+
4
[(OH)
 
3
|(PO
 
4
)
 
2
]
 
2
 · 3H
 
2
O
19.12.7Pararobertsite
Ca
 
2
Mn
3+
3
[O
 
2
|(PO
 
4
)
 
3
] · 3H
 
2
O
19.12.8Sinkankasite
H
 
2
Mn
2+
 
Al[OH|(PO
 
4
)
 
2
] · 6H
 
2
O
19.12.9Mangangordonite
Mn
2+
 
Al
 
2
[OH|PO
 
4
]
 
2
 · 8H
 
2
O
19.12.10Heterosite
(Fe
3+
 
,Mn
3+
 
)[PO
 
4
]
19.12.11Purpurite
(Mn
3+
 
,Fe
3+
 
)[PO
 
4
]
19.12.12Wolfeite
(Fe
2+
 
,Mn
2+
 
)
 
2
[OH|PO
 
4
]
19.12.13Triploidite
(Mn
2+
 
,Fe
2+
 
)
 
2
[OH|PO
 
4
]
19.12.14Lipscombite
(Fe
2+
 
,Mn
2+
 
)Fe
3+
2
[OH|PO
 
4
]
 
2
19.12.15Frondelite
Mn
2+
 
Fe
3+
4
[(OH)
 
5
|(PO
 
4
)
 
3
]
19.12.16Rockbridgeite
Fe
2+
 
Fe
3+
4
[(OH)
 
5
|(PO
 
4
)
 
3
]
19.12.17Kryzhanovskite
MnFe
 
2
(PO
 
4
)
 
2
(OH)
 
2
·H
 
2
O
19.12.18Landesite
Mn
2+
3-x
Fe
3+
x
[(OH)
 
x
|(PO
 
4
)
 
2
] · (3-x)H
 
2
O
19.12.19Phosphoferrite
(Fe,Mn)
 
3
(PO
 
4
)
 
2
·3H
 
2
O
19.12.20Reddingite
(Mn,Fe)
 
3
(PO
 
4
)
 
2
·3H
 
2
O
19.12.21Earlshannonite
Mn
2+
 
Fe
3+
2
(PO
 
4
)
 
2
(OH)
 
2
·4H
 
2
O
19.12.22Hureaulite
(Mn,Fe)
 
5
H
 
2
(PO
 
4
)
 
4
·4H
 
2
O
19.12.23Switzerite
(Mn,Fe)
 
3
(PO
 
4
)
 
2
·7H
 
2
O
19.12.24Laueite
Mn
2+
 
Fe
3+
2
[OH|PO
 
4
]
 
2
 · 8H
 
2
O
19.12.25Pseudolaueite
Mn
2+
 
Fe
3+
2
[OH|PO
 
4
]
 
2
 · 8H
 
2
O
19.12.26Strunzite
Mn
2+
 
Fe
3+
2
[OH|PO
 
4
]
 
2
 · 6H
 
2
O
19.12.27Stewartite
Mn
2+
 
Fe
3+
2
[OH|PO
 
4
]
 
2
 · 8H
 
2
O
19.12.28Alluaudite
(Na,Ca)Mn
2+
 
(Fe
3+
 
,Mn
2+
 
,Fe
2+
 
,Mg)
 
2
(PO
 
4
)
 
3
19.12.29Ferroalluaudite
(Na,Ca)Fe
2+
 
(Fe
3+
 
,Mn
2+
 
,Fe
2+
 
)
 
2
(PO
 
4
)
 
3
19.12.30Fillowite
{Mn
2+
 
}{Na
 
8
}{Ca
 
4
Na
 
4
}{(Mn
2+
 
,Fe
2+
 
)
 
43
}[PO
 
4
]
 
36
19.12.31Johnsomervilleite
{Ca}{Na
 
6
[ ]
 
2
}{Ca
 
6
Na
 
2
}{(Fe
2+
 
,Mg,Mn
2+
 
)
 
43
}[PO
 
4
]
 
36
19.12.32Wicksite
NaCa
 
2
(Fe
2+
 
,Mn
2+
 
)
 
4
MgFe
3+
 
[PO
 
4
]
 
6
 · 2H
 
2
O
19.12.33Dickinsonite-(KMnNa)
{KNa}{Mn
2+
 
[ ]}{Ca}{Na
 
3
}{Mn
2+
13
}{Al}[(OH)
 
2
|(PO
 
4
)
 
12
]
19.12.34Sarcopside
(Fe
2+
 
,Mn
2+
 
,Mg)
 
3
[PO
 
4
]
 
2
19.12.35Ludlamite
(Fe,Mn,Mg)
 
3
(PO
 
4
)
 
2
·4H
 
2
O
19.12.36Graftonite
(Fe
2+
 
,Mn
2+
 
,Ca)
 
3
[PO
 
4
]
 
2
19.12.37Wilhelmvierlingite
CaMnFe
3+
 
[OH|(PO
 
4
)
 
2
] · 2H
 
2
O
19.12.38Fairfieldite
Ca
 
2
(Mn
2+
 
,Fe
2+
 
)[PO
 
4
]
 
2
 · 2H
 
2
O
19.12.39Beusite
(Mn
2+
 
,Fe
2+
 
,Ca,Mg)
 
3
[PO
 
4
]
 
2
19.12.40Messelite
Ca
 
2
(Fe
2+
 
,Mn
2+
 
)[PO
 
4
]
 
2
 · 2H
 
2
O
19.12.42Jahnsite-(CaMnMn)
CaMn
2+
 
Mn
2+
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
19.12.43Jahnsite-(CaMnMg)
CaMn
2+
 
(Mg,Fe
2+
 
)
 
2
Fe
3+
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
19.12.44Keckite
(Ca,Mg)(Mn
2+
 
,Zn)
 
2
Fe
3+
3
(PO
 
4
)
 
4
(OH)
 
3
 · 2H
 
2
O
19.12.45Stanfieldite
Ca
 
7
Ca
 
2
Mg
 
9
[PO
 
4
]
 
12
19.12.46Laubmannite
(Fe
2+
 
,Mn
2+
 
,Ca)
 
3
Fe
3+
6
[(OH)
 
3
|PO
 
4
]
 
4
19.12.47Zodacite
Ca
 
4
Mn
2+
 
Fe
3+
4
[(OH)
 
2
|(PO
 
4
)
 
3
]
 
2
 · 12H
 
2
O
19.12.48Hagendorfite
NaCaMn
2+
 
Fe
2+
2
(PO
 
4
)
 
3
19.12.49Maghagendorfite
NaMn(Mg,Fe,Fe)
 
3
(PO
 
4
)
 
3
19.12.50Varulite
NaCaMn
2+
 
Mn
2+
2
(PO
 
4
)
 
3
19.12.51Griphite
Na
 
4
Li
 
2
Ca
 
6
(Mn
2+
 
,Fe
2+
 
,Mg)
 
19
Al
 
8
[(F,OH)|(PO
 
4
)
 
3
]
 
8
19.12.52Attakolite
(Ca,Sr)Mn(Al,Fe)
 
4
[(OH)
 
4
|(SiO
 
4
,PO
 
4
)|(HPO
 
4
,PO
 
4
)
 
3
]
19.12.53Arrojadite-(KFe)
{KNa}{Fe
2+
 
[ ]}{Ca}{Na
 
2
[ ]}{Fe
2+
13
}{Al}[(OH)
 
2
|HPO
 
4
|(PO
 
4
)
 
11
]
19.12.54Lun'okite
(Mn,Ca)(Mg,Fe,Mn)Al(PO
 
4
)
 
2
OH·4H
 
2
O
19.12.55Eosphorite
(Mn
2+
 
,Fe
2+
 
)Al[(OH)
 
2
|PO
 
4
] · H
 
2
O
19.12.56Ernstite
(Mn
2+
 
,Fe
3+
 
)Al[(OH,O)
 
2
|PO
 
4
] · H
 
2
O
19.12.57Childrenite
(Fe
2+
 
,Mn
2+
 
)Al[(OH)
 
2
|PO
 
4
] · H
 
2
O
19.12.58Bobfergusonite
Na
 
2
Mn
 
5
FeAl(PO
 
4
)
 
6
19.12.59Qingheiite
NaMn
3+
 
Mg(Al,Fe
3+
 
)[PO
 
4
]
 
3
19.12.60Whiteite-(CaFeMg)
Ca(Fe
2+
 
,Mn
2+
 
)Mg
 
2
Al
 
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
19.12.61Whiteite-(CaMnMg)
CaMn
2+
 
Mg
 
2
Al
 
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
19.12.62Whiteite-(MnFeMg)
(Mn
2+
 
,Ca)(Fe
2+
 
,Mn
2+
 
)Mg
 
2
Al
 
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
19.12.63Rittmannite
(Mn
2+
 
,Ca)Mn
2+
 
(Fe
2+
 
,Mn
2+
 
,Mg)
 
2
(Al,Fe
3+
 
)
 
2
(PO
 
4
)
 
4
(OH)
 
2
 · 8H
 
2
O
19.12.64Zanazziite
Ca
 
2
(Mg,Fe)(Mg,Fe,Al)
 
4
Be
 
4
[(OH)
 
4
|(PO
 
4
)
 
6
] · 6H
 
2
O
19.12.65Samuelsonite
(Ca,Ba)Ca
 
8
Fe
2+
2
Mn
2+
2
Al
 
2
[(OH)
 
2
|(PO
 
4
)
 
10
]

Other Names for Jahnsite-(CaMnFe)

Russian names:
Джансит-(CaMnFe)

Other Information

Health Warning:No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for Jahnsite-(CaMnFe)

Reference List:American Mineralogist: 59: 48-59, 964-973.

Mineralogical Magazine (1978): 42: 309-323.

Internet Links for Jahnsite-(CaMnFe)

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  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Search for Jahnsite-(CaMnFe) in the Natural History Museum (London) online catalogue
  • Jahnsite-(CaMnFe) details from Handbook of Mineralogy (PDF)
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    Localities for Jahnsite-(CaMnFe)

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    The 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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    (TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
    Brazil
     
    • Southeast Region
      • Minas Gerais
        • Doce valley
          • Galiléia
            • Sapucaia do Norte
    		Cassedanne, J.P. & Baptista, A. (1999): Famous Mineral Localities: The Sapucaia Pegmatite Minas Gerais, Brazil. Mineralogical Record, 30: 347-360 + 365
    Finland
     
    • Etelä-Suomen Lääni
      • Orivesi
        • Eräjärvi area
    Russia
     
    • Northern Region
      • Murmanskaja Oblast'
        • Kola Peninsula
    USA
     
    • Maine
      • Oxford Co.
        • Newry
    		V.T.King & E.E.Foord (1994), "Mineralogy of Maine",p201
    No reference listed
        • Paris
        • Rumford
    		King & Foord, 1994. Mineralogy of Maine, Vol.1, p.264.
    • New Hampshire
      • Grafton Co.
        • Groton
    		Moore and Ito (1978), Mineralogical Magazine: 42: 309-323 [316].
    No reference listed
    Journal of Pegmatology vol. 1, no. 1
    • North Carolina
      • Cleveland Co.
        • Kings Mountain District
    • South Dakota
      • Custer Co.
        • Custer District
          • Fourmile
    		No reference listed
    Mineral and/or Locality
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