Chopinite Mineral Data

General Chopinite Information

Chemical Formula:

(Mg,Fe)3(PO4)2

Composition:

Molecular Weight = 291.81 gm

Calcium 0.27 % Ca 0.38 % CaO

Magnesium 18.32 % Mg 30.39 % MgO

Manganese 0.19 % Mn 0.24 % MnO

Iron 16.46 % Fe 21.17 % FeO

Silicon 0.19 % Si 0.41 % SiO₂

Phosphorus 20.70 % P 47.43 % P₂O₅

Oxygen 43.86 % O

______ ______

100.00 % 100.03 % = TOTAL OXIDE

Empirical Formula:

Ca_0.02Mg_2.2Fe²⁺_0.86Mn²⁺_0.01Si_0.02P_1.95O₈

Environment:

Found in a fluorapatite segregation in a quartz mass roughly 10 cm thick and 3 m long in granulite-facies paragneiss. Mg-dominant analogue of sarcopside.

IMA Status:

Approved IMA 2006 (Dana # Added)

Locality:

Brattnevet Peninsula, Larsemann Hills, Prydz Bay, East Antarctica. Link to MinDat.org Location Data.

Name Origin:

Named for Christian Chopin, research director at Centre national de la recherche scientifique (CNRS).

Synonym:

IMA2006-004

Chopinite Crystallography

Axial Ratios:

a:b:c =1.2463:1:2.1555

Cell Dimensions:

a = 5.9305, b = 4.7583, c = 10.2566, Z = 2; beta = 90.663° V = 289.41 Den(Calc)= 3.35

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 2₁/c

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

By Intensity(I/I_o): 3.84(1), 2.51(0.59), 2.77(0.46),5.92(0.42), 2.44(0.4), 3.48(0.37), 4.31(0.29), 2.97(0.25),

Physical Properties of Chopinite

Color:

Colorless.

Habit:

Anhedral Grains - Granular minerals without the expression of crystal shapes

Luster:

Vitreous (Glassy)

Streak:

shite

Optical Properties of Chopinite

Gladstone-Dale:

CI calc= 0.003 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.189,KC= 0.1895
Ncalc = 1.63

Optical Data:

Biaxial (-), a=1.595, b=1.648, g=1.656, bire=0.0610

Calculated Properties of Chopinite

Electron Density:

Bulk Density (Electron Density)=3.28 gm/cc
note: Specific Gravity of Chopinite =3.35 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Chopinite= 6.37 barns/electron
U=PE_Chopinite x rElectron Density= 20.92 barns/cc.

Radioactivity:

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

Chopinite Classification

Dana Class:

38.03.01.03 (38)Anhydrous Phosphates, etc

(38.03)(A+ B++)3 (XO4)2

(38.03.01)Sarcopside Group

38.03.01.01 Sarcopside (Fe,Mn,Mg)3(PO4)2 P 2₁/a 2/m

38.03.01.02 Farringtonite Mg3(PO4)2 P 2₁/a 2/m

38.03.01.03 Chopinite! (Mg,Fe)3(PO4)2 P 2₁/c 2/m

Strunz Class:

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

08.A - Phosphates, etc. without additional anions, without H2O

08.AB -With medium-sized cations

08.AB.15 Sarcopside (Fe,Mn,Mg)3(PO4)2 P 2₁/a 2/m

08.AB.15 Chopinite! (Mg,Fe)3(PO4)2 P 2₁/c 2/m

Other Chopinite Information

References:

NAME( AmMin, v93:252) PHYS. PROP.(AmMin, v93:252) OPTIC PROP.(AmMin, v93:252)

See Also:

Links to other databases for Chopinite :
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

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Print or Cut-and-Paste your Chopinite Specimen Label here :

Chopinite

(Mg,Fe)3(PO4)2
Dana No: 38.03.01.03 Strunz No: 08.AB.15
Locality:

Notes:

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