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Andyrobertsite Mineral Data

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General Andyrobertsite Information

Help on Chemical  Formula: Chemical Formula: KCdCu5(AsO4)4[As(OH)2O2]•2(H2O)
Help on Composition: Composition: Molecular Weight = 1,201.88 gm
   Potassium   3.25 %  K     3.92 % K2O
   Cadmium     9.35 %  Cd   10.68 % CdO
   Copper     26.44 %  Cu   33.09 % CuO
   Arsenic    31.17 %  As   47.81 % As2O5
   Hydrogen    0.50 %  H     4.50 % H2O
   Oxygen     29.29 %  O
             ______        ______ 
             100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: KCdCu5(AsO4)4(As(OH)2O2)•2(H2O)
Help on Environment: Environment: Single specimen found at the mine. Forms a series with calcioandyrobertsite.
Help on IMA Status: IMA Status: Approved IMA 1999 (Dana # Added)
Help on Locality: Locality: Tsumeb Mine, Tsumeb, Namibia. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named after Andrew C. Roberts (1950-), mineralogist with the Geological Survey of Canada, specialist in documentation of new mineral species, in particular from low-temperature seco ndary parageneses.
Help on Name Pronunciation: Name Pronunciation: Andyrobertsite + Pronunciation Say ANDYROBERTSITE
Help on Synonym: Synonym: ICSD 89894

Andyrobertsite Image

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Comments: Blue andyrobertsite with blue calcioandyrobertsite on green olivenite. Holotype specimen Min Record cover.
Location: Tsumeb Mine, Tsumeb, Namibia.. Scale: Specimen 4.1 cm.
© William Pinch

Andyrobertsite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.9776:1:0.9941
Help on Cell Dimensions: Cell Dimensions: a = 9.81, b = 10.034, c = 9.975, Z = 2; beta = 101.84° V = 960.98 Den(Calc)= 4.15
Help on Crystal System: Crystal System: Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 21/m
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 9.64(1), 3.145(0.5), 4.46(0.4),

Physical Properties of Andyrobertsite

Help on Cleavage: Cleavage: {100} Good
Help on Color: Color: Electric blue.
Help on Density: Density: 4.011
Help on Diaphaneity: Diaphaneity: Transparent
Help on Fracture: Fracture: Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.
Help on Habit: Habit: Platy - Sheet forms (e.g. micas).
Help on Hardness: Hardness: 3 - Calcite
Help on Luster: Luster: Vitreous (Glassy)
Help on Streak: Streak: pale blue

Optical Properties of Andyrobertsite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.085 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.048 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1788,KPDmeas= 0.185,KC= 0.1706
Ncalc = 1.68 - 1.71
Help on Optical Data: Optical Data: Biaxial (-), a=1.72, b=1.749, g=1.757, bire=0.0370

Calculated Properties of Andyrobertsite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=3.86 gm/cc
note: Specific Gravity of Andyrobertsite =4.15 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.02
Boson Index = 0.98
Help on Photoelectric: Photoelectric: PEAndyrobertsite = 58.24 barns/electron
U=PEAndyrobertsite x relectron= 224.84 barns/cc.
Help on Radioactivity: Radioactivity:

GRapi = 43.68 (Gamma Ray American Petroleum Institute Units)
Concentration of Andyrobertsite per GRapi unit = 2.29 (%)

Estimated Radioactivity from Andyrobertsite - barely detectable


Andyrobertsite Classification

Help on  Dana Class: Dana Class: (42)Hydrated Phosphates, etc., Containing Hydroxyl or Halogen
  (42.09)where (A)3 (XO4)2 Zq � x(H2O)
  (42.09.02)Souzalite Group Souzalite (Mg,Fe)3(Al,Fe)4(PO4)4(OH)6•2(H2O) P1,P 1 Tri Gormanite Fe3Al4(PO4)4(OH)6•2(H2O) P1,P 1 Tri Andyrobertsite! KCdCu5(AsO4)4[As(OH)2O2]•2(H2O) P 21/m 2/m Calcioandyrobertsite-1M! KCaCu5(AsO4)4[As(OH)2O2]•2(H2O) P 21/m 2/m Calcioandyrobertsite-2O! KCaCu5(AsO4)4[As(OH)2O2]•2(H2O) P nma 2/m 2/m 2/m
Help on  Strunz Class: Strunz Class: 08.DH.50 08 - PHOSPHATES, ARSENATES, VANADATES
  08.D - Phosphates, etc
  08.DH -With large and medium-sized cations, (OH, etc.):RO4 < 1:1
08.DH.50 Andyrobertsite! KCdCu5(AsO4)4[As(OH)2O2]•2(H2O) P 21/m 2/m
08.DH.50 Calcioandyrobertsite-1M! KCaCu5(AsO4)4[As(OH)2O2]•2(H2O) P 21/m 2/m
08.DH.50 Calcioandyrobertsite-2O! KCaCu5(AsO4)4[As(OH)2O2]•2(H2O) P nma 2/m 2/m 2/m

Other Andyrobertsite Information

Help on References: References: NAME( MinRec, Vol 30) PHYS. PROP.(MinRec, Vol 30) OPTIC PROP.(MinRec, Vol 30)
Help on See Also: See Also: Links to other databases for Andyrobertsite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - Handbook of Mineralogy (UofA)
7 - MinDAT
8 - Mineralienatlas (Deutsch)
9 - Online Mineral Museum
10 - QUT Mineral Atlas
11 - Ruff.Info

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Dana No: Strunz No: 08.DH.50





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