Cobaltarthurite Mineral Data

General Cobaltarthurite Information

Chemical Formula:

CoFe+++2(AsO4)2(OH)2•4(H2O)

Composition:

Molecular Weight = 533.48 gm

Magnesium 0.46 % Mg 0.76 % MgO

Manganese 1.03 % Mn 1.33 % MnO

Iron 21.98 % Fe 31.43 % Fe₂O₃

Cobalt 5.52 % Co 7.02 % CoO

Arsenic 28.09 % As 43.08 % As₂O₅

Hydrogen 1.83 % H 16.38 % H₂O

Oxygen 41.09 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Co_0.5Mg_0.1Fe³⁺_0.1Mn²⁺_0.1Fe³⁺₂(AsO₄)₂(OH)_1.7·4(H₂O)

Environment:

Secondary mineral in a near surface, sulfide-depleted lens (Dolores showing). (Co-dominant analogue of arthurite; structure)

IMA Status:

Approved IMA 2002 (Dana # Added)

Locality:

Patrana (a village about 10 km east of Mazzarron), Province of Murcia, SE Spain. Link to MinDat.org Location Data.

Name Origin:

Named as the Co-dominant member of the arthurite group.

Synonym:

IMA2001-052

Cobaltarthurite Image

Images:

Click Here for Larger Cobaltarthurite Image

Cobaltarthurite Arseniosiderite

Comments: Olive-greenish crystalline druse of cobaltarthurite with spherical arseniosiderite.
Location: Pastrana, MazarrÃ³n, Murcia, Spain. Scale: Picture size 1.3 mm.
© Thomas Witzke / Abraxas-Verlag

Cobaltarthurite Crystallography

Axial Ratios:

a:b:c =1.0577:1:0.5741

Cell Dimensions:

a = 10.2635, b = 9.7028, c = 5.5711, Z = 2; beta = 94.207° V = 553.30 Den(Calc)= 3.20

Crystal System:

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

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

By Intensity(I/I_o): 7.04(1)(110), 10.2(0.95)(100), 4.81(0.65)(001),3.05(0.6), 4.24(0.6)(111), 2.87(0.55)(311), 2.89(0.25)(221), 4.51(0.2),

Crystal Structure:

Mouse
drag1 - LMB Manipulate Structure
drag2 - RMB Resize/Rotate
Keyboard
S - Stereo Pair on/off
H - Help Screen
I - Data Info
A - Atoms On/Off
P - Polyhedra On/Off
B - Bonds On/Off
Help on Above

Raudsepp M , Pani E , The Canadian Mineralogist , 40 (2002) p.733-737, The crystal structure of cobaltarthurite, CoFe2(AsO4)2(OH)2.4H2O:, A Rietveld refinement

View Additional jPOWD Structure files for Cobaltarthurite
[1]

Physical Properties of Cobaltarthurite

Cleavage:

None

Color:

Straw yellow, Dark brown.

Density:

3.22

Diaphaneity:

Translucent

Fracture:

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

Habit:

Globular - Spherical, or nearly so, rounded forms (e.g. wavellite).

Habit:

Massive - Uniformly indistinguishable crystals forming large masses.

Habit:

Oolitic - < 3mm rounded spherical grains.

Hardness:

3.5-4 - Copper Penny-Fluorite

Luster:

Vitreous - Silky

Streak:

light brownish white

Optical Properties of Cobaltarthurite

Gladstone-Dale:

CI meas= 0.013 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.007 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2396,KPDmeas= 0.2381,KC= 0.2412
Ncalc = 1.77 - 1.78

Optical Data:

Biaxial (+), a=1.741, b=1.762, g=1.797, bire=0.0560

Calculated Properties of Cobaltarthurite

Electron Density:

Bulk Density (Electron Density)=3.08 gm/cc
note: Specific Gravity of Cobaltarthurite =3.20 gm/cc.

Fermion Index:

Fermion Index = 0.0053160916
Boson Index = 0.9946839084

Photoelectric:

PE_{Cobaltarthurite}= 27.71 barns/electron
U=PE_{Cobaltarthurite} x rElectron Density= 85.48 barns/cc.

Radioactivity:

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

Cobaltarthurite Classification

Dana Class:

42.11.18.06 (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 Cobaltarthurite Information

References:

NAME( AmMin, Vol 88, p 475) PHYS. PROP.(AmMin, v88, p475; v91, p715) OPTIC PROP.(AmMin, Vol 88, p 475)

See Also:

Links to other databases for Cobaltarthurite :
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 Cobaltarthurite using:

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

Visit our Advertisers for Cobaltarthurite :

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

Ask about Cobaltarthurite 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 Cobaltarthurite Specimen Label here :

Cobaltarthurite

CoFe+++2(AsO4)2(OH)2•4(H2O)
Dana No: 42.11.18.06 Strunz No: 08.DC.15
Locality:

Notes: