Gengenbachite Mineral Data

General Gengenbachite Information

Chemical Formula:

KFe3(H2PO4)2(HPO4)4•6H2O or KFe3H8(PO4)6•6H2O

Composition:

Molecular Weight = 892.62 gm

Potassium 4.38 % K 5.28 % K₂O

Iron 18.77 % Fe 24.15 % FeO

Phosphorus 20.82 % P 47.71 % P₂O₅

Hydrogen 2.26 % H 20.18 % H₂O

Oxygen 53.77 % O

______ ______

100.00 % 97.31 % = TOTAL OXIDE

Empirical Formula:

KFe²⁺₃H₈(PO₄)₆•6(H₂O)

IMA Status:

Proposed IMA 2006

Locality:

Grube Silberbrünnle, Haigerach Valley near Gengenbach, Central Black Forest, Germany Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Synonym:

IMA2001-003b

Search for Gengenbachite Images

Images:

Image not yet available on Webmineral.com

Try searching images.google.com or Mindat Picture Gallary for mineral pictures. Caution: The images retrieved may not be appropriate.

Gengenbachite Crystallography

Axial Ratios:

a:c = 1:1.84649

Cell Dimensions:

a = 9.12, c = 16.84, V = 1,213.00

Crystal System:

Hexagonal - Dihexagonal PyramidalH-M Symbol (6mm) Space Group: P 6₃mc

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

By Intensity(I/I_o): 7.16(1), 3.09(0.8), 4.57(0.7),3.23(0.6), 2.81(0.5), 3.57(0.5), 2.87(0.4), 7.89(0.4),

Optical Properties of Gengenbachite

Optical Data:

Calculated Properties of Gengenbachite

Fermion Index:

Fermion Index = 0.0042458883
Boson Index = 0.9957541117

Photoelectric:

PE_{Gengenbachite}= 6.94 barns/electron
U=PE_{Gengenbachite} x r_electron= . barns/cc.

Radioactivity:

GRapi = 63.29 (Gamma Ray American Petroleum Institute Units)
Concentration of Gengenbachite per GRapi unit = 1.58 (%)

Estimated Radioactivity from Gengenbachite - barely detectable

Gengenbachite Classification

Dana Class:

37.00.00.00 (37)Phosphate Minerals

(37.00)Without Dana Classification Numbers

(37.00.00)Phosphate, Basic Hydrated

37.00.00.00 Arnhemite* (K,Na)2Mg2(P2O7)•5(H2O) Unk Hex

37.00.00.00 Arsenowaylandite* BiAl3(AsO4)2(OH)6 R 3m 3 2/m

37.00.00.00 Auroantimonate* AuSbO3 Ortho ? Ortho

37.00.00.00 Barium-zinc-alumopharmacosiderite* (Ba,K)0.5(Zn,Cu)0.5(Al,Fe)4(AsO4)3•5(H2O) I 42m 4 2m

37.00.00.00 Chernovite-(Ce)* (Ce,Y)(AsO4) I 4₁/amd 4/m 2/m 2/m

37.00.00.00 Churchite-(Dy)* (Dy,Sm,Gd,Nd)(PO4)•2(H2O) Mono

37.00.00.00 Gengenbachite KFe3(H2PO4)2(HPO4)4•6H2OorKFe3H8(PO4)6•6H2O P 6₃mc 6mm

37.00.00.00 IMA2008-063 Pb[Zn0.25,[]0.75]Fe3H(AsO4)2(OH)6 C 2/c 2/m

37.00.00.00 IMA2009-005 (Y,Ca,REE)5[(Si,P)O4]3F P 6₃/m 6/m 2/m 2/m

37.00.00.00 IMA2009-016 Cu4H(AsO4)2(OH)3•H2O P1 1

37.00.00.00 Kerstenite? PbSeO4(?) P nma 2/m 2/m 2/m

37.00.00.00 Krasnoselskite* CoWO4 P 2/c 2/m

37.00.00.00 Laubmannite? Fe3Fe6(PO4)4(OH)12 Unk Ortho

37.00.00.00 Oxiberaunite* (Fe,Mn)Fe5(PO4)4O(OH)4•6(H2O) Mono

37.00.00.00 Parwanite (Na,K)(Mg,Ca)4Al8(PO4)8(CO3)(OH)7•30H2O P 2, Pm, P 2/m, P 2₁, Mono

37.00.00.00 Pyrocoproite* (Mg(K,Na))2P2O7 Unk Mono

37.00.00.00 Pyrophosphite* K2CaP2O7 P 2₁/n 2/m

37.00.00.00 Zinclavendulan? NaCa(Zn,Cu)5(AsO4)4Cl•4-5(H2O) Unk Ortho

Strunz Class:

08.CA.65 08 - PHOSPHATES, ARSENATES, VANADATES

08.C - Phosphates without Additional Anions, with H2O

08.CA -With small and large/medium cations

08.CA.65 Gengenbachite KFe3(H2PO4)2(HPO4)4•6H2OorKFe3H8(PO4)6•6H2O P 6₃mc 6mm

Other Gengenbachite Information

See Also:

Links to other databases for Gengenbachite :
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

Search for Gengenbachite using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Gengenbachite :

A Bijoux Google Search for Gengenbachite
Adam's Minerals Google Search for Gengenbachite
Cape Minerals Google Search for Gengenbachite
Dakota Matrix Minerals Google Search for Gengenbachite
Excalibur Mineral Corp. Google Search for Gengenbachite
Exceptional Minerals Google Search for Gengenbachite
John Betts Fine Minerals Search for Gengenbachite
McDougall Minerals Google Search for Gengenbachite
Mineral News Website Link
Rock and Mineral Shows Google Search for Gengenbachite
Weinrich Minerals, Inc. Google Search for Gengenbachite

Ask about Gengenbachite here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in Español

Print or Cut-and-Paste your Gengenbachite Specimen Label here :

Gengenbachite

KFe3(H2PO4)2(HPO4)4•6H2O or KFe3H8(PO4)6•6H2O
Dana No: 37.00.00.00 Strunz No: 08.CA.65
Locality:

Notes: