Helmutwinklerite Mineral Data

General Helmutwinklerite Information

Chemical Formula:

PbZn2(AsO4)2•2(H2O)

Composition:

Molecular Weight = 651.85 gm

Zinc 20.06 % Zn 24.97 % ZnO

Arsenic 22.99 % As 35.26 % As₂O₅

Hydrogen 0.62 % H 5.53 % H₂O

Lead 31.79 % Pb 34.24 % PbO

Oxygen 24.54 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

PbZn₂(AsO₄)₂•2(H₂O)

Environment:

Rare secondary mineral in corroded tennantite ore from a dolostone-hosted hydrothermal polymetallic ore deposit.

IMA Status:

Approved IMA 1980

Locality:

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

Name Origin:

Named for Helmut G.F. Winkler (1915-1980), University of Gottingen, Gottingen, Germany

Name Pronunciation:

Helmutwinklerite + Pronunciation

Synonym:

ICSD 76617

PDF 33-781

Helmutwinklerite Crystallography

Axial Ratios:

a:b:c =0.9992:1:1.3577

Cell Dimensions:

a = 5.606, b = 5.61, c = 7.617, Z = 1; alpha = 70.19°, beta = 69.91°, gamma = 69.18° V = 197.84 Den(Calc)= 5.47

Crystal System:

Triclinic - Pinacoidal H-M Symbol ( 1) Space Group: P1

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

By Intensity(I/I_o): 3.071(1), 4.698(0.72), 3.279(0.69),

Physical Properties of Helmutwinklerite

Cleavage:

None

Color:

Colorless, Sky blue.

Density:

5.3

Hardness:

4.5 - Between Fluorite and Apatite

Luster:

Vitreous - Resinous

Streak:

white

Optical Properties of Helmutwinklerite

Gladstone-Dale:

CI meas= 0.005 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.007 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1598,KPDmeas= 0.1601,KC= 0.1609
Ncalc = 1.85

Optical Data:

Biaxial (+), a=1.72-1.83, b=1.8-1.87, g=1.89-1.98, bire=0.1500-0.1700, 2V(Calc)=66-88, 2V(Meas)=70.

Calculated Properties of Helmutwinklerite

Electron Density:

Bulk Density (Electron Density)=4.75 gm/cc
note: Specific Gravity of Helmutwinklerite =5.30 gm/cc.

Fermion Index:

Fermion Index = 0.07
Boson Index = 0.93

Photoelectric:

PE_{Helmutwinklerite}= 571.97 barns/electron
U=PE_{Helmutwinklerite} x rElectron Density=2,715.93 barns/cc.

Radioactivity:

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

Helmutwinklerite Classification

Dana Class:

40.02.09.02 (40)Hydrated Phosphates, etc

(40.02)where A++ (B++)2 (XO4) ï¿½ x(H2O)

(40.02.09)Helmutwinklerite Subgroup

40.02.09.01 Tsumcorite PbZnFe(AsO4)2•(H2O) C 2/m 2/m

40.02.09.02 Helmutwinklerite PbZn2(AsO4)2•2(H2O) P1 1

40.02.09.03 Thometzekite Pb(Cu,Zn)2(AsO4)2•2(H2O) C 2/m 2/m

40.02.09.04 Mawbyite Pb(FeZn)2(AsO4)2(OH,H2O)2 C 2/m 2/m

40.02.09.05 Rappoldite! Pb(Co,Ni,Zn,)2(AsO4)2•2(H2O) P1 1

40.02.09.06 Schneebergite! Bi(Co,Ni)2(AsO4)2(OH,H2O)2 C 2/m 2/m

40.02.09.07 Nickelschneebergite! Bi(Ni,Co)2(AsO4)2(OH,H2O)2 C 2/m 2/m

40.02.09.08 Cobalttsumcorite! Pb(Co,Fe)2(AsO4)2(OH,H2O)2 C 2/m 2/m

Strunz Class:

08.CG.20 08 - PHOSPHATES, ARSENATES, VANADATES

08.C - Phosphates without Additional Anions, with H2O

08.CG -With large and medium-sized cations, RO4:H2O = 1:1

08.CG.20 Gartrellite Pb(Cu,Fe)2(AsO4,SO4)2(CO3,H2O)0.7 P1,P 1 Tri

08.CG.20 Helmutwinklerite PbZn2(AsO4)2•2(H2O) P1 1

08.CG.20 Phosphogartrellite! PbCuFe(PO4)2(OH,H2O)2 P1 1

08.CG.20 Zincgartrellite! Pb(Zn,Fe,Cu)2(AsO4)2(OH,H2O)2 P1 1

08.CG.20 Rappoldite! Pb(Co,Ni,Zn,)2(AsO4)2•2(H2O) P1 1

08.CG.20 Lukrahnite! Ca(Cu,Zn)(Fe,Zn)(AsO4)2(OH,H2O)2 P1 1

Other Helmutwinklerite 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 Helmutwinklerite :
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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Helmutwinklerite

PbZn2(AsO4)2•2(H2O)
Dana No: 40.02.09.02 Strunz No: 08.CG.20
Locality:

Notes:

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