Walthierite Mineral Data

General Walthierite Information

Chemical Formula:

Ba0.5Al3(SO4)2(OH)6

Composition:

Molecular Weight = 443.78 gm

Barium 15.47 % Ba 17.28 % BaO

Aluminum 18.24 % Al 34.46 % Al₂O₃

Hydrogen 1.36 % H 12.18 % H₂O

Sulfur 14.45 % S 36.08 % SO₃

Oxygen 50.47 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Ba_0.5Al₃(SO₄)₂(OH)₆

Environment:

Open-space filling of a fault, formed by reaction of hydrothermal fluids with barite.

IMA Status:

Approved IMA 1992

Locality:

Reina vein, about seven km southeast of the El Indio mine, El Indio-Tambo district, east of La Serena, Coquimbo, Chile. Link to MinDat.org Location Data.

Name Origin:

Named for Thomas Nash Walthier (1923-1990), American economic geologist, St. Joseph Minerals Co., who worked in the Tambo district, Chile.

Name Pronunciation:

Walthierite + Pronunciation

Synonym:

IMA1991-008

Walthierite Image

Images:

Walthierite

Comments: SEM BSE image of subhedral and euhedral walthierite (light gray) enclosed within alunite (dark gray). (AmMin, v77:1275).
Location: El Indio gold, silver, and copper deposit, Tambo mining district, Coquimbo region, Chile. Scale: See Image.
© American Mineralogist

Walthierite Crystallography

Axial Ratios:

a:c = 1:4.92605

Cell Dimensions:

a = 6.992, c = 34.443, Z = 6; V = 1,458.26 Den(Calc)= 3.03

Crystal System:

Trigonal - Hexagonal Scalenohedral H-M Symbol (3 2/m) Space Group: R 3m

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

By Intensity(I/I_o): 2.98(1), 2.283(0.8), 1.909(0.7),

Physical Properties of Walthierite

Cleavage:

{???} Perfect

Color:

White, Yellowish.

Diaphaneity:

Transparent

Hardness:

3-4 - Calcite-Fluorite

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Walthierite

Gladstone-Dale:

CI calc= 0.01 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1967,KC= 0.1987
Ncalc = 1.6

Optical Data:

Uniaxial (+), w=1.588, e=1.604, bire=0.0160.

Calculated Properties of Walthierite

Electron Density:

Bulk Density (Electron Density)=2.96 gm/cc
note: Specific Gravity of Walthierite =3.03 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Walthierite= 64.89 barns/electron
U=PE_Walthierite x rElectron Density= 192.29 barns/cc.

Radioactivity:

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

Walthierite Classification

Dana Class:

30.02.04.07 (30)Anhydrous Sulfates Containing Hydroxyl or Halogen

(30.02)where (A B)2 XO4 Zq

(30.02.04)Alunite Group (Alunite Subgroup)

30.02.04.01 Alunite KAl3(SO4)2(OH)6 R 3m, R 3m Trig

30.02.04.02 Natroalunite NaAl3(SO4)2(OH)6 R 3m 3 2/m

30.02.04.03 Schlossmacherite (H3O,Ca)Al3(AsO4,SO4)2(OH)6 R 3m 3 2/m

30.02.04.04 Osarizawaite PbCuAl2(SO4)2(OH)6 R 3m 3m

30.02.04.05 Minamiite (Na,Ca,K)Al3(SO4)2(OH)6 R 3m 3 2/m

30.02.04.06 Ammonioalunite (NH4)Al3(SO4)2(OH)6 R 3m 3 2/m

30.02.04.07 Walthierite Ba0.5Al3(SO4)2(OH)6 R 3m 3 2/m

30.02.04.08 Huangite Ca0.5Al3(SO4)2(OH)6 R 3m 3 2/m

Strunz Class:

07.BC.10 07 - SULFATES (SELENATES, TELLURATES)

07.B - Sulfates (selenates, etc.) with Additional Anions, without H2O

07.BC -With medium-sized and large cations

07.BC.10 Alunite KAl3(SO4)2(OH)6 R 3m, R 3m Trig

07.BC.10 Ammonioalunite (NH4)Al3(SO4)2(OH)6 R 3m 3 2/m

07.BC.10 Ammoniojarosite (NH4)Fe3(SO4)2(OH)6 R 3m 3m

07.BC.10 Beaverite PbCu(Fe,Al)2(SO4)2(OH)6 R 3m 3m

07.BC.10 Argentojarosite AgFe3(SO4)2(OH)6 R 3m 3m

07.BC.10 Huangite Ca0.5Al3(SO4)2(OH)6 R 3m 3 2/m

07.BC.10 Dorallcharite (Tl,K)Fe3(SO4)2(OH)6 R 3m 3 2/m

07.BC.10 Jarosite KFe3(SO4)2(OH)6 R 3 3

07.BC.10 Hydroniumjarosite (H3O)Fe3(SO4)2(OH)6 R 3m 3m

07.BC.10 Minamiite (Na,Ca,K)Al3(SO4)2(OH)6 R 3m 3 2/m

07.BC.10 Natrojarosite NaFe3(SO4)2(OH)6 R 3m 3m

07.BC.10 Natroalunite NaAl3(SO4)2(OH)6 R 3m 3 2/m

07.BC.10 Osarizawaite PbCuAl2(SO4)2(OH)6 R 3m 3m

07.BC.10 Plumbojarosite PbFe6(SO4)4(OH)12 R 3m 3 2/m

07.BC.10 Schlossmacherite (H3O,Ca)Al3(AsO4,SO4)2(OH)6 R 3m 3 2/m

07.BC.10 Walthierite Ba0.5Al3(SO4)2(OH)6 R 3m 3 2/m

Other Walthierite Information

References:

NAME( AntBidBlaNic5) PHYS. PROP.(Am.Min.,Vol.77,p1275-1284,1992) OPTIC PROP.(Am.Min.,Vol.77,p1275-1284,1992)

See Also:

Links to other databases for Walthierite :
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 - MinDAT
10 - Mineralienatlas (Deutsch)
11 - Online Mineral Museum
12 - QUT Mineral Atlas
13 - Ruff.Info

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Walthierite

Ba0.5Al3(SO4)2(OH)6
Dana No: 30.02.04.07 Strunz No: 07.BC.10
Locality:

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