Sherwoodite Mineral Data

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General Sherwoodite Information

Chemical Formula:

Ca9Al2V++++4V+++++24O80•56(H2O)

Composition:

Molecular Weight = 4,129.83 gm

Calcium 8.73 % Ca 12.22 % CaO

Aluminum 1.31 % Al 2.47 % Al₂O₃

Vanadium 34.54 % V 61.66 % V₂O₅

Hydrogen 2.73 % H 24.43 % H₂O

Oxygen 52.69 % O

______ ______

100.00 % 100.77 % = TOTAL OXIDE

Empirical Formula:

Ca₉Al₂V⁵⁺₄V⁵⁺₂₄O₈₀•56(H₂O)

Environment:

Oxidation product of lower valent vanadium minerals, on fracture surfaces and replacing fossil wood in Colorado Plateau-type U–V deposits.

IMA Status:

Valid Species (Pre-IMA) 1958

Locality:

Peanut and Jo Dandy mines, Bull Canyon district, Uravan district, Montrose Co., Colorado, USA. Link to MinDat.org Location Data.

Name Origin:

Named for Alexander M. Sherwood (1888-?), American analytical chemist, U.S. Geological Survey.

Name Pronunciation:

Sherwoodite + Pronunciation

Synonym:

ICSD 100660

PDF 11-191

Sherwoodite Image

Images:

Sherwoodite

Comments: Dark blackish-violet sherwoodite, altering to translucent green, crystalline crust.
Location: San Juan County, Colorado, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Sherwoodite Crystallography

Axial Ratios:

a:c = 1:0.48325

Cell Dimensions:

a = 28.06, c = 13.56, Z = 4; V = 10,676.65 Den(Calc)= 2.57

Crystal System:

Tetragonal - Ditetragonal DipyramidalH-M Symbol (4/m 2/m 2/m) Space Group: I 4₁/amd

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

By Intensity(I/I_o): 10(1), 12.3(1), 9.3(0.8),

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
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Evans H T , Konnert J A , American Mineralogist , 63 (1978) p.863-868, The crystal chemistry of sherwoodite, a calcium 14-vanadoaluminate heteropoly, complex

Physical Properties of Sherwoodite

Cleavage:

None

Color:

Blue green, Yellow green, Dark blue black.

Density:

2.8

Fracture:

Conchoidal - Uneven - Uneven fracture producing small, conchoidal fragments.

Hardness:

2 - Gypsum

Luster:

Vitreous - Dull

Streak:

light blue

Optical Properties of Sherwoodite

Gladstone-Dale:

CI meas= 0.172 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= 0.098 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2918,KPDmeas= 0.2679,KC= 0.3235
Ncalc = 1.83 - 1.91

Optical Data:

Uniaxial (-), e=1.735, w=1.765, bire=0.0300.

Calculated Properties of Sherwoodite

Electron Density:

Bulk Density (Electron Density)=2.55 gm/cc
note: Specific Gravity of Sherwoodite =2.57 gm/cc.

Fermion Index:

Fermion Index = 0.0012383612
Boson Index = 0.9987616388

Photoelectric:

PE_Sherwoodite= 7.60 barns/electron
U=PE_Sherwoodite x rElectron Density= 19.39 barns/cc.

Radioactivity:

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

Sherwoodite Classification

Dana Class:

47.02.04.01 (47)Vanadium Oxysalts

(47.02)(VmOn)

(47.02.04)Dana Group

47.02.04.01 Sherwoodite Ca9Al2V4V24O80•56(H2O) I 4₁/amd 4/m 2/m 2/m

Strunz Class:

04.HC.15 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.H - V[5,6] Vanadates

04.HC -[6]-Sorovanadates

04.HC.15 Sherwoodite Ca9Al2V4V24O80•56(H2O) I 4₁/amd 4/m 2/m 2/m

Other Sherwoodite Information

References:

NAME( AntBidBlaNic4) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Sherwoodite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info
15 - WWW-MINCRYST

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Translate Sherwoodite Mineral Data :

Ask about Sherwoodite here :
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Print or Cut-and-Paste your Sherwoodite Specimen Label here :

Sherwoodite

Ca9Al2V++++4V+++++24O80•56(H2O)
Dana No: 47.02.04.01 Strunz No: 04.HC.15
Locality:

Notes: