Andyrobertsite Mineral Data

Andyrobertsite Mineral Data +

[Mineral Specimens] [Our best] [Rare specimens] [Latest updates] [Home Page]
Fine Minerals, Moldavites, Jewellery, Meteorites and Fossils
Rockshop.cz is based in Prague, Czech republic

General Andyrobertsite Information

Chemical Formula:

KCdCu5(AsO4)4[As(OH)2O2]·2(H2O)

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

Empirical Formula:

KCdCu₅(AsO₄)₄(As(OH)2O2)·2(H₂O)

Environment:

Single specimen found at the mine. Forms a series with calcioandyrobertsite.

IMA Status:

Approved IMA 1999 (Dana # Added)

Locality:

Tsumeb Mine, Tsumeb, Namibia. Link to MinDat.org Location Data.

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.

Synonym:

ICSD 89894

IMA1997-023

Search for Andyrobertsite Images

Images:

Image not yet available on Webmineral.com

Try searching images.google.com or Mindat Picture Gallary for mineral pictures. Caution: The images retrieved may not be appropriate.

Andyrobertsite Crystallography

Axial Ratios:

a:b:c =0.9776:1:0.9941

Cell Dimensions:

a = 9.81, b = 10.034, c = 9.975, Z = 2; beta = 101.84° V = 960.98 Den(Calc)= 4.15

Crystal System:

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

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

By Intensity(I/I_o): 9.64(1), 3.145(0.5), 4.46(0.4),

Physical Properties of Andyrobertsite

Cleavage:

[100] Good

Color:

Electric blue.

Density:

4.011

Diaphaniety:

Transparent

Fracture:

Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.

Habit:

Platy - Sheet forms (e.g. micas).

Hardness:

3 - Calcite

Luster:

Vitreous (Glassy)

Streak:

pale blue

Optical Properties of Andyrobertsite

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

Optical Data:

Biaxial (-), a=1.72, b=1.749, g=1.757, bire=0.0370

Calculated Properties of Andyrobertsite

Electron Density:

r_electron=3.86 gm/cc
note: r_{Andyrobertsite}=4.15 gm/cc.

Fermion Index

Fermion Index = 0.02355
Boson Index = 0.97645

Photoelectric:

PE_{Andyrobertsite}= 58.24 barns/electron
U=PE_{Andyrobertsite} x r_electron= 224.84 barns/cc.

Radioactivity:

GRapi = 43.68 (Gamma Ray American Petroleum Institute Units)

Estimated Radioactivity from Andyrobertsite - barely detectable

Andyrobertsite Classification

Dana Class:

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

(42.9)where (A)3 (XO4)2 Zq · x(H2O)

(42.9.2)Dana Group

42.9.2.1 Souzalite (Mg,Fe)3(Al,Fe)4(PO4)4(OH)6·2(H2O) P1,P 1 Tri

42.9.2.2 Gormanite Fe3Al4(PO4)4(OH)6·2(H2O) P1,P 1 Tri

42.9.2.3 Andyrobertsite ! KCdCu5(AsO4)4[As(OH)2O2]·2(H2O) P 2₁/m 2/m

42.9.2.4 Calcio-andyrobertsite-1M! KCaCu5(AsO4)4[As(OH)2O2]·2(H2O) P 2₁/m 2/m

42.9.2.5 Calcio-andyrobertsite-2O! KCaCu5(AsO4)4[As(OH)2O2]·2(H2O) P nma 2/m 2/m 2/m

Strunz Class:

VII/D.25-35 VII - Phosphates, Arsenates and Vanadates

VII/D - Water-bearing phosphates with unfamiliar anions, cations of very big and medium size: Al, Mg and Ca, Na, K

VII/D.25 - Lavendulan series

VII/D.25-10 Sampleite NaCaCu5(PO4)4Cl·5(H2O) pseudo TET 2/m 2/m 2/m

VII/D.25-20 Lavendulan NaCaCu5(AsO4)4Cl·5(H2O) Unk Ortho

VII/D.25-22 Zinclavendulan* NaCa(Zn,Cu)5(AsO4)4Cl·4-5(H2O) Unk Ortho

VII/D.25-24 Lemanskiite! NaCaCu5(AsO4)4Cl·5(H2O) P 4₁22 or P 4₃22 Tetra

VII/D.25-25 Zdenekite NaPbCu5(AsO4)4Cl·5(H2O) P 4₁22,P 4₃22 4 2 2

VII/D.25-27 Mahnertite! (Na,Ca)Cu3(AsO4)2Cl·5(H2O) I 4mmm 4 2 2

VII/D.25-30 Shubnikovite Ca2Cu8(AsO4)6Cl(OH)·7(H2O)(?) Unk Ortho

VII/D.25-33 Goldquarryite! (Cu,[])(Cd,Ca)2Al3(PO4)4F2(H2O)10{(H2O,F)}2 P1 1

VII/D.25-35 Andyrobertsite KCdCu5(AsO4)4[As(OH)2O2]·2(H2O) P 2₁/m 2/m

VII/D.25-36 Calcio-andyrobertsite-1M! KCaCu5(AsO4)4[As(OH)2O2]·2(H2O) P 2₁/m 2/m

VII/D.25-36* Calcio-andyrobertsite-2O! KCaCu5(AsO4)4[As(OH)2O2]·2(H2O) P nma 2/m 2/m 2/m

VII/D.25-38 Esperanzaite! NaCa2Al2(AsO4)2F4(OH)·2(H2O) P 2₁/m 2/m

VII/D.25-40 Englishite K3Na2Ca10Al15(PO4)21(OH)7·26(H2O) A2 or Aa 2

Other Andyrobertsite Information

References:

NAME( MinRec, Vol 30) PHYS. PROP.(MinRec, Vol 30) OPTIC PROP.(MinRec, Vol 30)

See Also:

Links to other databases for Andyrobertsite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 -Google Images 4 -Google Scholar 5 -Handbook of Mineralogy (UofA) 6 -MinDAT 7 -MinMax(Deutsch) 8 -MinMax(English) 9 -Mineralienatlas (Deutsch) 10 -QUT Mineral Atlas

Search for Andyrobertsite using:

[ALTAVISTA] [AOL] [About.com] [All-The-Web] [HotBot] [Ixquick] [LookSmart] [MAMMA] [MSN.COM] [Netscape] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Andyrobertsite :
AA Mineral Specimens
B and L Minerals
Dan Weinrich Fine Minerals
Dan Weinrich Auctions
e-Rocks Auctions
Excalibur Minerals
Exceptional Minerals
Fabre Minerals
Greenside Minerals
John Betts Fine Minerals
Masons Minerals
Minernet.it
Mineral News
Mineral of the Month Club
MineralsWeb Fine Minerals
Rockshop.cz Kalat Fine Minerals
T G Fine Minerals
Wrights Rock Shop

Translate Andyrobertsite Mineral Data :

Ask about Andyrobertsite 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 Andyrobertsite Specimen Label here :

Andyrobertsite

KCdCu5(AsO4)4[As(OH)2O2]·2(H2O)
Dana No: 42.9.2.3 Strunz No: VII/D.25-35
Locality:

Notes: