Petewilliamsite Mineral Data
General Petewilliamsite Information
Chemical Formula:
(Ni,Co,Cu)30(As2O7)15
Composition:
Molecular Weight = 5,730.36 gm
Calcium 0.12 % Ca 0.17 % CaO
Iron 0.03 % Fe 0.04 % FeO
Cobalt 14.21 % Co 18.07 % CoO
Copper 2.67 % Cu 3.35 % CuO
Nickel 15.01 % Ni 19.11 % NiO
Arsenic 38.64 % As 59.26 % As2 O5
Oxygen 29.32 % O
______ ______
100.00 % 99.99 % = TOTAL OXIDE
Empirical Formula:
Ni14.66 Co13.82 Cu2.41 Ca0.17 Fe2+ 0.03 15(As1.97 )15(O7 )
Environment:
In a fine-grained quartz specimen. It is the only known natural pyroarsenate.
IMA Status:
Approved IMA 2004 (Dana # Added)
Locality:
Johanngeorgenstadt, Saxony, Germany. Link to MinDat.org Location Data.
Name Origin:
Named for Peter (Pete) Allan Williams (b. 1950), Professor, Minerals and Materials Group, School of Science, Food and Horticulture, University of Western Sydney, Penrith South DC, N ew South Wales, Australia.
Synonym:
IMA2002-059
Petewilliamsite Image
Images:
Petewilliamsite
Comments: SEM image of a portion of a petewilliamsite aggregate. Note the rounded nature of the crystal faces. (Min. Mag. 68:235).
Location: Johanngeorgenstadt, Saxony, Germany.
Scale: See Image.
© Mineralogical Magazine
Petewilliamsite Crystallography
Axial Ratios:
a:b:c =3.9208:1:1.6731
Cell Dimensions:
a = 33.256, b = 8.4818, c = 14.191, Z = 1; beta = 104.145° V = 3,881.50 Den(Calc)= 2.45
Crystal System:
Monoclinic - Sphenoidal H-M Symbol (2) Space Group: C 2
X Ray Diffraction:
By Intensity(I/Io ): 3.118(1)(513,023), 3.005(0.6)(10 .0.3), 1.637(0.5)(536), 2.567(0.5)(10 .2.0), 1.507(0.3)(553,15.3.3,2 04.235(0.3)(020),
Physical Properties of Petewilliamsite
Cleavage:
None
Color:
Dark violet red, Dark brownish red.
Diaphaneity:
Translucent
Fracture:
Brittle - Uneven - Very brittle fracture producing uneven fragments.
Habit:
Aggregates - Made of numerous individual crystals or clusters.
Hardness:
1.5-2.5 - Hardness very near Gypsum
Luster:
Vitreous - Adamantine
Streak:
pale reddish brown
Optical Properties of Petewilliamsite
Optical Data:
NCalc= 1.41 - from Gladstone-Dale relationship (KC = 0.1681) where Ncalc =Dcalc *KC +1
RL Anisotrophism:
Not obvious.
RL Bireflectance:
None.
RL Color:
Dark gray with orange internal reflections.
RL Pleochroism:
None.
Reflectivity
Standardized Intensity (100%) Reflection Spectra of Petewilliamsite in Air
λ
R
∑ R (λ)
400 nm
9.84
420 nm
9.85
440 nm
9.71
460 nm
9.63
470 nm
9.59
480 nm
9.55
500 nm
9.49
520 nm
9.39
540 nm
9.33
546 nm
9.32
560 nm
9.29
580 nm
9.33
589 nm
9.27
600 nm
9.33
620 nm
9.29
640 nm
9.33
650 nm
9.33
660 nm
9.32
680 nm
9.31
700 nm
9.30
Calculated Relative Intensity Colors of Petewilliamsite in Air
Relative Intensity
0%
100%
200%
300%
400%
500%
600%
700%
800%
900%
940%
R
Calculated Properties of Petewilliamsite
Electron Density:
Bulk Density (Electron Density)=2.29 gm/cc note: Specific Gravity of Petewilliamsite =2.45 gm/cc.
Fermion Index:
Fermion Index = 0.0018451825 Boson Index = 0.9981548175
Photoelectric:
PEPetewilliamsite = 39.26 barns/electronU=PEPetewilliamsite x r Electron Density= 89.74 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Petewilliamsite is Not Radioactive
Petewilliamsite Classification
Dana Class:
38.04.13.01 (38) Anhydrous Phosphates, etc
(38.04) A+ XO4
(38.04.13) Dana Group
38.04.13.01 Petewilliamsite ! (Ni,Co,Cu)30(As2O7)15 C 2 2
Strunz Class:
08.FA.25 08 - PHOSPHATES, ARSENATES, VANADATES
08.F - Polyphosphates, Polyarsenates, [4]-Polyvanadates
08.FA -Polyphosphates, etc., without OH and H2O; dimers of corner-sharing RO4 tetrahedra.
08.FA.25 Petewilliamsite ! (Ni,Co,Cu)30(As2O7)15 C 2 2
Other Petewilliamsite Information
References:
NAME( CanMin, 42:1922) PHYS. PROP.(CanMin, 42:1922) OPTIC PROP.(MinMag, 68:235)
See Also:
Links to other databases for Petewilliamsite :
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 Petewilliamsite using:
[AOL ]
[Bing ]
[Dog Pile ]
[GeoScienceWorld ]
[HotBot ]
[Ixquick ]
[Lycos ]
[MAMMA ]
[Scirus ]
[Teoma ]
[WebCrawler ]
[Wikipedia ]
[YAHOO ]
Visit our Advertisers for Petewilliamsite :
Ask about Petewilliamsite 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
Espa�ol
Print or Cut-and-Paste your Petewilliamsite Specimen Label here :
Petewilliamsite
(Ni,Co,Cu)30(As2O7)15
Dana No: 38.04.13.01 Strunz No: 08.FA.25
Locality:
Notes:
Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.