Birchite Mineral Data

General Birchite Information

Chemical Formula:

Cd2Cu2(PO4)2(SO4)•5H2O

Composition:

Molecular Weight = 741.06 gm

Calcium 0.11 % Ca 0.15 % CaO

Manganese 0.15 % Mn 0.19 % MnO

Zinc 0.88 % Zn 1.10 % ZnO

Cadmium 31.70 % Cd 36.22 % CdO

Copper 16.64 % Cu 20.82 % CuO

Phosphorus 8.65 % P 19.82 % P₂O₅

Hydrogen 1.36 % H 12.16 % H₂O

Sulfur 3.81 % S 9.51 % SO₃

Oxygen 36.70 % O

______ ______

100.00 % 99.97 % = TOTAL OXIDE

Empirical Formula:

Cu_1.94P_2.07S_0.88O₁₂•5(H₂O)Zn_0.1Cd_2.09Ca_0.02Mn²⁺_0.02

Environment:

Late-stage supergene mineral formed as part of a suite of secondary phosphate minerals under low-temperature conditions. New structure type.

IMA Status:

Approved IMA 2006 (Dana # Added)

Locality:

Block 14 Opencut, Broken Hill, New South Wales, Australia Link to MinDat.org Location Data.

Name Origin:

Named for William D. Birch, Senior Curator of Geosciences at Museum Victoria, Australia, in recognition of his contribution to Australian geological sciences.

Synonym:

IMA2006-048

Birchite Image

Images:

Birchite

Comments: SEM image showing bladed crystals of birchite on anglesite. The crystals are flattened on (100) and show the principal forms {100}, {010}, and {101}. (AmMin, v93:912).
Location: Block 14 Opencut, Broken Hill, New South Wales, Australia. Scale: Scale Bar 50µm.
© American Mineralogist

Birchite Crystallography

Axial Ratios:

a:b:c =0.5018:1:0.2944

Cell Dimensions:

a = 10.489, b = 20.901, c = 6.155, Z = 4; V = 1,349.36 Den(Calc)= 3.65

Crystal System:

Orthorhombic - DipyramidalH-M Symbol (2/m 2/m 2/m) Space Group: P nma

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

By Intensity(I/I_o): 10.451(1)(020), 1.919(0.8)(432), 2.902(0.7)(260),3.484(0.39)(060), 4.223(0.38)(131), 2.719(0.33)(132), 2.652(0.32)(042), 5.146(0.28)(111),

Crystal Structure:

Mouse
drag1 - LMB Manipulate Structure
drag2 - RMB Resize/Rotate
Keyboard
S - Stereo Pair on/off
H - Help Screen
I - Data Info
A - Atoms On/Off
P - Polyhedra On/Off
B - Bonds On/Off
Help on Above

Elliot P , Brugger J , Pring A , Cole M L , Willis A C , Kolitsch U , American Mineralogist , 93 (2008) p.910-917, Birchite, a new mineral from Broken Hill, New South Wales, Australia:, Description and structure refinement, Locality: Block 14 Opencut, Broken Hill, New South Wales, Australia

Physical Properties of Birchite

Color:

Pale blue.

Density:

3.61

Diaphaneity:

Translucent to transparent

Fracture:

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

Habit:

Aggregates - Made of numerous individual crystals or clusters.

Habit:

Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).

Hardness:

3.5-4 - Copper Penny-Fluorite

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Birchite

Gladstone-Dale:

CI meas= 0.007 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.018 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1762,KPDmeas= 0.1781,KC= 0.1793
Ncalc = 1.65

Optical Data:

Biaxial (+), a=1.624, b=1.636, g=1.669, bire=0.0450

Calculated Properties of Birchite

Electron Density:

Bulk Density (Electron Density)=3.43 gm/cc
note: Specific Gravity of Birchite =3.61 gm/cc.

Fermion Index:

Fermion Index = 0.08
Boson Index = 0.92

Photoelectric:

PE_Birchite= 89.11 barns/electron
U=PE_Birchite x rElectron Density= 305.26 barns/cc.

Radioactivity:

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

Birchite Classification

Dana Class:

43.05.12.02 (43)Compound Phosphates, etc.

(43.05)(Hydrated Compound Anions With Hydroxyl or Halogen)

(43.05.12)Synadelphite Group

43.05.12.01 Synadelphite (Mn,Mg,Ca,Pb)9(AsO3)(AsO4)2(OH)9•2(H2O)(?) P nma 2/m 2/m 2/m

43.05.12.02 Birchite! Cd2Cu2(PO4)2(SO4)•5H2O P nma 2/m 2/m 2/m

Strunz Class:

08.DB.70 08 - PHOSPHATES, ARSENATES, VANADATES

08.D - Phosphates, etc

08.DB -With only medium-sized cations, (OH, etc.):RO4 < 1:1

08.DB.70 Birchite! Cd2Cu2(PO4)2(SO4)•5H2O P nma 2/m 2/m 2/m

Other Birchite Information

References:

NAME( AmMin, v93:910) PHYS. PROP.(AmMin, v93:910) OPTIC PROP.(AmMin, v93:910)

See Also:

Links to other databases for Birchite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info

Search for Birchite using:

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

Visit our Advertisers for Birchite :

A Bijoux Google Search for Birchite
Adam's Minerals Google Search for Birchite
Cape Minerals Google Search for Birchite
Dakota Matrix Minerals Google Search for Birchite
Excalibur Mineral Corp. Google Search for Birchite
Exceptional Minerals Google Search for Birchite
John Betts Fine Minerals Search for Birchite
McDougall Minerals Google Search for Birchite
Mineral News Website Link
Rock and Mineral Shows Google Search for Birchite
Weinrich Minerals, Inc. Google Search for Birchite

Ask about Birchite 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 Birchite Specimen Label here :

Birchite

Cd2Cu2(PO4)2(SO4)•5H2O
Dana No: 43.05.12.02 Strunz No: 08.DB.70
Locality:

Notes: