Jahnsite-(CaMnFe) Mineral Data

General Jahnsite-(CaMnFe) Information

Chemical Formula:

CaMn++Fe++2Fe+++2(PO4)4(OH)2•8(H2O)

Composition:

Molecular Weight = 876.43 gm

Calcium 4.57 % Ca 6.40 % CaO

Manganese 6.27 % Mn 8.09 % MnO

Iron 25.49 % Fe 16.40 % FeO / 18.22 % Fe₂O₃

Phosphorus 14.14 % P 32.39 % P₂O₅

Hydrogen 2.07 % H 18.50 % H₂O

Oxygen 47.46 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

CaMn²⁺Fe²⁺₂Fe³⁺₂(PO₄)₄(OH)₂•8(H₂O)

IMA Status:

Approved IMA 1978

Locality:

Fletcher mine, North Groton, New Hampsire, USA. Link to MinDat.org Location Data.

Name Origin:

Named for Richard H. Jahns (1915-1983), mineralogist and pegmatite expert, Stanford University, Palo Alto, California, USA.

Name Pronunciation:

Jahnsite-(CaMnFe)

Jahnsite-(CaMnFe) Image

Images:

Jahnsite-(CaMnFe)

Comments: Orange-brown microcrystalline jahnsite-(CaMnFe) associated with quartz.
Location: Voron'i Tundry, Kola Peninsula, Murmanskaja Oblast', Northern Region, Russia. Scale: See Image.
© Rruff Database

Jahnsite-(CaMnFe) Crystallography

Axial Ratios:

a:b:c =2.0993:1:1.3804

Cell Dimensions:

a = 15.01, b = 7.15, c = 9.87, Z = 2; beta = 111.23° V = 987.38 Den(Calc)= 2.95

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: P 2/a

$Help on X Ray Diffraction:$ X Ray Diffraction:

By Intensity(I/I_o): 9.15(1), 2.81(0.5), 4.6(0.4),3.45(0.3), 3.48(0.3), 1.874(0.2), 4.96(0.2), 4.84(0.1),

Physical Properties of Jahnsite-(CaMnFe)

Cleavage:

{001} Good

Color:

Brown, Purplish brown, Yellow, Yellow orange.

Density:

2.86

Diaphaneity:

Transparent to Translucent

Fracture:

Brittle - Generally displayed by glasses and most non-metallic minerals.

Hardness:

4 - Fluorite

Luster:

Vitreous - Adamantine

Streak:

white

Optical Properties of Jahnsite-(CaMnFe)

Optical Data:

NCalc= 1.71 - from Gladstone-Dale relationship (KC = 0.2398) where Ncalc=Dcalc*KC+1
NCalc= 1.69 - from Gladstone-Dale relationship (KC = 0.2398) where Ncalc=Dmeas*KC+1

Calculated Properties of Jahnsite-(CaMnFe)

Electron Density:

Bulk Density (Electron Density)=2.93 gm/cc
note: Specific Gravity of Jahnsite-(CaMnFe) =2.95 gm/cc.

Fermion Index:

Fermion Index = 0.0056962282
Boson Index = 0.9943037718

Photoelectric:

PE_{Jahnsite-(CaMnFe)}= 10.33 barns/electron
U=PE_{Jahnsite-(CaMnFe)} x rElectron Density= 30.24 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Jahnsite-(CaMnFe) is Not Radioactive

Jahnsite-(CaMnFe) Classification

Dana Class:

42.11.02.02 (42)Hydrated Phosphates, etc., Containing Hydroxyl or Halogen

(42.11)where (AB)4 (XO4)3 Zq · x(H2O)

(42.11.02)Jahnsite Group

42.11.02.01 Jahnsite-(CaMnMg) CaMnMg2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

42.11.02.02 Jahnsite-(CaMnFe) CaMnFe2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

42.11.02.03 Jahnsite-(CaMnMn) CaMnMn2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

42.11.02.04 Jahnsite-(MnMnMn)* MnMnMn2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

Strunz Class:

08.DH.15 08 - PHOSPHATES, ARSENATES, VANADATES

08.D - Phosphates, etc

08.DH -With large and medium-sized cations, (OH, etc.):RO4 < 1:1

08.DH.15 Keckite Ca(Mn,Zn)2Fe3(PO4)4(OH)3•2(H2O) P 2₁/a 2/m

08.DH.15 Jahnsite-(CaMnFe) CaMnFe2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

08.DH.15 Jahnsite-(CaMnMg) CaMnMg2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

08.DH.15 Jahnsite-(CaMnMn) CaMnMn2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

08.DH.15 Jahnsite-(MnMnMn)* MnMnMn2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

08.DH.15 Kaluginite* (Mn,Ca)MgFe(PO4)2(OH)•4(H2O) C cca 2/m 2/m 2/m

08.DH.15 Rittmannite MnMnFeAl2(OH)2(PO4)4•8(H2O) P 2/a 2/m

08.DH.15 Whiteite-(MnFeMg) (Mn,Ca)(Fe,Mn)Mg2Al2(PO4)4(OH)2•8(H2O) P 2/a 2/m

08.DH.15 Whiteite-(CaFeMg) Ca(Fe,Mn)Mg2Al2(PO4)4(OH)2•8(H2O) P 2₁/a 2/m

08.DH.15 Whiteite-(CaMnMg) CaMnMg2Al2(PO4)4(OH)2•8(H2O) P 2/a 2/m

08.DH.15 Jahnsite-(CaFeFe)! (Ca,Mn)(Fe,Mn)Fe2Fe2(PO4)4(OH)2•8(H2O) P 2/a 2/m

08.DH.15 Jahnsite-(NaFeMg)! NaFeMg2Fe2(PO4)4(OH)2•8H2O P 2/a 2/m

08.DH.15 Jahnsite-(CaMgMg)! CaMgMg2Fe2(PO4)4(OH)2•8H2O P 2/a 2/m

08.DH.15 Jahnsite-(NaMnMg)! NaMnMg2Fe2(PO4)4(OH)2•8H2O P 2/a 2/m

Other Jahnsite-(CaMnFe) Information

References:

NAME( Dana8) PHYS. PROP.(Dana8)

See Also:

Links to other databases for Jahnsite-(CaMnFe) :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info

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Print or Cut-and-Paste your Jahnsite-(CaMnFe) Specimen Label here :

Jahnsite-(CaMnFe)

CaMn++Fe++2Fe+++2(PO4)4(OH)2•8(H2O)
Dana No: 42.11.02.02 Strunz No: 08.DH.15
Locality:

Notes: