Mixite Mineral Data

General Mixite Information

Chemical Formula:

BiCu6(AsO4)3(OH)6•3(H2O)

Composition:

Molecular Weight = 1,163.10 gm

Copper 32.78 % Cu 41.03 % CuO

Bismuth 17.97 % Bi 20.03 % Bi₂O₃

Arsenic 19.32 % As 29.64 % As₂O₅

Hydrogen 1.04 % H 9.29 % H₂O

Oxygen 28.89 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

BiCu₆(AsO₄)₃(OH)₆•3(H₂O)

Environment:

Secondary mineral in bismuth-bearing ores.

IMA Status:

Valid Species (Pre-IMA) 1880

Locality:

Jï¿½chymov (St Joachimsthal), Krusne Hory (Erzgebirge), Zï¿½padoceskï¿½ Kraj, Bohemia, Czech Republic Link to MinDat.org Location Data.

Name Origin:

Named after the mining engineer, A. Mixa from Jachymov, Czechoslovakia.

Name Pronunciation:

Mixite

Synonym:

ICSD 70117

PDF 13-414

Mixite Image

Images:

Mixite

Comments: Vuggy quartz matrix with green radial sprays of mixite crystals.
Location: Northern Star mine, Tintic district, Utah, USA. Scale: 6 x 5 x 4 cm.
© John Veevaert

Mixite Crystallography

Axial Ratios:

a:c = 1:0.43286

Cell Dimensions:

a = 13.63, c = 5.9, Z = 2; V = 949.24 Den(Calc)= 4.07

Crystal System:

Hexagonal - Dipyramidal H-M Symbol (6/m) Space Group: P 6₃/m

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

By Intensity(I/I_o): 12(1), 2.46(0.9), 3.57(0.8),

Physical Properties of Mixite

Color:

Blue green, Yellow green, White, Light blue, Light green.

Density:

3.8

Fracture:

Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.

Habit:

Acicular - Occurs as needle-like crystals.

Habit:

Encrustations - Forms crust-like aggregates on matrix.

Habit:

Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite)

Hardness:

3.5-4 - Copper Penny-Fluorite

Luminescence:

Non-fluorescent.

Luster:

Adamantine

Magnetism:

Nonmagnetic

Streak:

pale green

Optical Properties of Mixite

Dichroism (e):

almost colorless.

Dichroism (w):

fine green.

Gladstone-Dale:

CI meas= -0.126 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.051 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1892,KPDmeas= 0.2026,KC= 0.18
Ncalc = 1.68 - 1.73

Optical Data:

Uniaxial (+), w=1.73, e=1.81, bire=0.0800.

Calculated Properties of Mixite

Electron Density:

Bulk Density (Electron Density)=3.75 gm/cc
note: Specific Gravity of Mixite =4.07 gm/cc.

Fermion Index:

Fermion Index = 0.0001403978
Boson Index = 0.9998596022

Photoelectric:

PE_Mixite= 342.30 barns/electron
U=PE_Mixite x rElectron Density=1,284.05 barns/cc.

Radioactivity:

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

Mixite Classification

Dana Class:

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

(42.05)where (A)2 (XO4) Zq ï¿½ x(H2O)

(42.05.01)Mixite group (Arsenate Series)

42.05.01.01 Mixite BiCu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

42.05.01.02 Agardite-(Y) (Y,Ca)Cu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

42.05.01.02a Agardite-(La)! (La,Ca)Cu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

42.05.01.02b Agardite-(Nd)! (Pb,Nd,Y,La,Ca)Cu6(AsO4)3(OH)6•3(H2O) 6/m

42.05.01.02c Agardite-(Dy)! (Dy,La,Ca)Cu6(AsO4)3(OH)6•3(H2O) 6/m

42.05.01.02d Agardite-(Ca)! CaCu6(AsO4)3(OH)6•3(H2O) 6/m

42.05.01.02e Agardite-(Ce)! (Ce,Ca)Cu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

42.05.01.03 Goudeyite (Al,Y)Cu6(AsO4)3(OH)6•3(H2O) Unk Hex

42.05.01.04 Zalesiite! (Ca,Y)Cu6[(AsO4)2(AsO3OH)(OH)6]•3(H2O) P 6₃/m 6/m

42.05.01.06 Plumboagardite! (Pb,REE,Ca)Cu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

Strunz Class:

08.DL.15 08 - PHOSPHATES, ARSENATES, VANADATES

08.D - Phosphates, etc

08.DL -With large and medium-sized cations, (OH, etc.):RO4 = 2:1

08.DL.15 Agardite-(Dy)! (Dy,La,Ca)Cu6(AsO4)3(OH)6•3(H2O) 6/m

08.DL.15 Agardite-(Ca)! CaCu6(AsO4)3(OH)6•3(H2O) 6/m

08.DL.15 Agardite-(Ce)! (Ce,Ca)Cu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

08.DL.15 Agardite-(La)! (La,Ca)Cu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

08.DL.15 Agardite-(Nd)! (Pb,Nd,Y,La,Ca)Cu6(AsO4)3(OH)6•3(H2O) 6/m

08.DL.15 Agardite-(Y) (Y,Ca)Cu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

08.DL.15 Goudeyite (Al,Y)Cu6(AsO4)3(OH)6•3(H2O) Unk Hex

08.DL.15 Zalesiite! (Ca,Y)Cu6[(AsO4)2(AsO3OH)(OH)6]•3(H2O) P 6₃/m 6/m

08.DL.15 Mixite BiCu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

08.DL.15 Petersite-(Y) (Y,Ce,Nd,Ca)Cu6(PO4)3(OH)6•3(H2O) P 6₃/m 6/m

08.DL.15 Calciopetersite! CaCu6[(PO4)2(PO3OH)(OH)6]•3(H2O) P 6₃/m 6/m

08.DL.15 Plumboagardite! (Pb,REE,Ca)Cu6(AsO4)3(OH)6•3(H2O) P 6₃/m 6/m

Other Mixite Information

References:

NAME( Duda&Rejl90) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Ford32)

See Also:

Links to other databases for Mixite :
1 - Am. Min. Crystal Structure Database
2 - Amethyst Galleries' Mineral Gallery
3 - Athena
4 - EUROmin Project
5 - Ecole des Mines de Paris
6 - GeoScienceWorld
7 - Google Images
8 - Google Scholar
9 - Handbook of Mineralogy (MinSocAm)
10 - Handbook of Mineralogy (UofA)
11 - MinDAT
12 - Mineralienatlas (Deutsch)
13 - Online Mineral Museum
14 - QUT Mineral Atlas
15 - Ruff.Info
16 - WWW-MINCRYST

Search for Mixite using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Mixite :

Ask about Mixite 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 Mixite Specimen Label here :

Mixite

BiCu6(AsO4)3(OH)6•3(H2O)
Dana No: 42.05.01.01 Strunz No: 08.DL.15
Locality:

Notes:

Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.