Bahianite Mineral Data

General Bahianite Information

Chemical Formula:

Al5Sb+++++3O14(OH)2

Composition:

Molecular Weight = 758.16 gm

Aluminum 17.79 % Al 33.62 % Al₂O₃

Antimony 48.18 % Sb 64.00 % Sb₂O₅

Hydrogen 0.27 % H 2.38 % H₂O

Oxygen 33.76 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Al₅Sb₃O₁₄(OH)₂

Environment:

In potholes as stream-worn pebbles and as residual concentrates above weathered volcanic rock.

IMA Status:

Approved IMA 1974

Locality:

About eight km southeast of the village of Paramirim das Crioulas, and elsewhere in the region around Rio do Picos das Almas, Serra das Almas, south-central Bahia, Brazil. Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Name Pronunciation:

Bahianite + Pronunciation

Synonym:

ICSD 14050

PDF 29-2

Bahianite Image

Images:

Bahianite

Comments: Rounded grain of bahianite.
Location: Garimpo de Morro, Paramirim Region, Bahia, Brazil. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Bahianite Crystallography

Axial Ratios:

a:b:c =0.815:1:0.3821

Cell Dimensions:

a = 9.406, b = 11.541, c = 4.41, Z = 2; beta = 90.94° V = 478.66 Den(Calc)= 5.26

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: C 2/m

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

By Intensity(I/I_o): 3.194(1), 3.24(1), 2.156(0.8),

Physical Properties of Bahianite

Cleavage:

{100} Perfect

Color:

Colorless, Violet, Cream white, Light brown.

Density:

4.89 - 5.46, Average = 5.17

Diaphaneity:

Transparent

Hardness:

9 - Corundum

Luster:

Adamantine

Streak:

white

Optical Properties of Bahianite

Gladstone-Dale:

CI meas= 0.046 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= 0.062 (Fair) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1648,KPDmeas= 0.1675,KC= 0.1756
Ncalc = 1.86 - 1.96

Optical Data:

Biaxial (-), a=1.81, b=1.87, g=1.92, bire=0.1100

Calculated Properties of Bahianite

Electron Density:

Bulk Density (Electron Density)=4.75 gm/cc
note: Specific Gravity of Bahianite =5.18 gm/cc.

Fermion Index:

Fermion Index = 0.0001624685
Boson Index = 0.9998375315

Photoelectric:

PE_Bahianite= 154.92 barns/electron
U=PE_Bahianite x rElectron Density= 735.98 barns/cc.

Radioactivity:

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

Bahianite Classification

Dana Class:

44.03.07.01 (44)Antimonates

(44.03)with miscellaneous formulae

(44.03.07)Dana Group

44.03.07.01 Bahianite Al5Sb3O14(OH)2 C 2/m 2/m

Strunz Class:

04.DC.05 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.D - Metal:Oxygen = 1:2 and similar

04.DC -With medium-sized cations; sheets of edge-sharing octahedra

04.DC.05 Bahianite Al5Sb3O14(OH)2 C 2/m 2/m

Other Bahianite 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 Bahianite :
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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Print or Cut-and-Paste your Bahianite Specimen Label here :

Bahianite

Al5Sb+++++3O14(OH)2
Dana No: 44.03.07.01 Strunz No: 04.DC.05
Locality:

Notes:

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