Bendadaite Mineral Data

General Bendadaite Information

Chemical Formula:

Fe++Fe+++2(AsO4)2(OH)2•4H2O

Composition:

Molecular Weight = 551.46 gm

Iron 30.38 % Fe 13.03 % FeO / 28.96 % Fe₂O₃

Arsenic 27.17 % As 41.68 % As₂O₅

Hydrogen 1.83 % H 16.33 % H₂O

Oxygen 40.62 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Fe²⁺Fe³⁺₂(AsO₄)₂(OH)₂•4(H₂O)

Environment:

Whitmoreite group

IMA Status:

Proposed IMA 2007 (Dana # Added)

Locality:

Bendada near Guarda, province Beira Alta, central Portugal Link to MinDat.org Location Data.

Name Origin:

Named for the locality

Synonym:

IMA1998-053a

Bendadaite Crystallography

Axial Ratios:

a:b:c =1.0541:1:0.5716

Cell Dimensions:

a = 10.239, b = 9.713, c = 5.552, Z = 2; beta = 94.11° V = 550.73 Den(Calc)= 3.33

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 2₁/c

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

By Intensity(I/I_o): 10.22(1), 7.036(0.8), 4.25(0.5),2.865(0.4), 2.907(0.3), 4.833(0.3), 3.49(0.2), 4.52(0.2),

Optical Properties of Bendadaite

Optical Data:

NCalc= 1.8 - from Gladstone-Dale relationship (KC = 0.2388) where Ncalc=Dcalc*KC+1

Calculated Properties of Bendadaite

Electron Density:

Bulk Density (Electron Density)=3.21 gm/cc
note: Specific Gravity of Bendadaite =3.33 gm/cc.

Fermion Index:

Fermion Index = 0.0066386119
Boson Index = 0.9933613881

Photoelectric:

PE_Bendadaite= 27.45 barns/electron
U=PE_Bendadaite x rElectron Density= 88.20 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Bendadaite is Not Radioactive

Bendadaite Classification

Dana Class:

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

(42.11)where (AB)4 (XO4)3 Zq � x(H2O)

(42.11.18)Whitmoreite Group

42.11.18.01 Whitmoreite FeFe2(PO4)2(OH)2•4(H2O) P 2₁/c 2/m

42.11.18.02 Arthurite CuFe2(AsO4,PO4,SO4)2(O,OH)2•4(H2O) P 2₁/c 2/m

42.11.18.03 Ojuelaite ZnFe2(AsO4)2(OH)2•4(H2O) P 2₁/c 2/m

42.11.18.04 Earlshannonite (Mn,Fe)Fe2(PO4)2(OH)2•4(H2O) P 2₁/c 2/m

42.11.18.05 Gladiusite! Fe2(Fe,Mg)4(PO4)(OH)13•H2O P 2₁/n 2/m

42.11.18.06 Cobaltarthurite! CoFe2(AsO4)2(OH)2•4(H2O) P 2₁/c 2/m

42.11.18.07 Kunatite CuFe2(PO4)2(OH)2•4H2O P 2₁/c 2/m

42.11.18.08 Bendadaite! FeFe2(AsO4)2(OH)2•4H2O P 2₁/c 2/m

Strunz Class:

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

08.D - Phosphates, etc

08.DC -With only medium-sized cations, (OH, etc.):RO4 = 1:1 and < 2:1

08.DC.15 Earlshannonite (Mn,Fe)Fe2(PO4)2(OH)2•4(H2O) P 2₁/c 2/m

08.DC.15 Arthurite CuFe2(AsO4,PO4,SO4)2(O,OH)2•4(H2O) P 2₁/c 2/m

08.DC.15 Ojuelaite ZnFe2(AsO4)2(OH)2•4(H2O) P 2₁/c 2/m

08.DC.15 Whitmoreite FeFe2(PO4)2(OH)2•4(H2O) P 2₁/c 2/m

08.DC.15 Cobaltarthurite! CoFe2(AsO4)2(OH)2•4(H2O) P 2₁/c 2/m

08.DC.15 Kunatite CuFe2(PO4)2(OH)2•4H2O P 2₁/c 2/m

08.DC.15 Bendadaite! FeFe2(AsO4)2(OH)2•4H2O P 2₁/c 2/m

Other Bendadaite Information

See Also:

Links to other databases for Bendadaite :
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 Bendadaite Specimen Label here :

Bendadaite

Fe++Fe+++2(AsO4)2(OH)2•4H2O
Dana No: 42.11.18.08 Strunz No: 08.DC.15
Locality:

Notes:

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