Despujolsite Mineral Data

General Despujolsite Information

Chemical Formula:

Ca3Mn++++(SO4)2(OH)6•3(H2O)

Composition:

Molecular Weight = 523.39 gm

Calcium 22.97 % Ca 32.14 % CaO

Manganese 10.50 % Mn 16.61 % MnO₂

Hydrogen 2.31 % H 20.65 % H₂O

Sulfur 12.25 % S 30.59 % SO₃

Oxygen 51.97 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Ca₃Mn⁴⁺(SO₄)₂(OH)₆•3(H₂O)

Environment:

Hydrothermal manganese deposit.

IMA Status:

Approved IMA 1968

Locality:

Tachgagalt, Morocco. Link to MinDat.org Location Data.

Name Origin:

Named for Pierre Despujols (1888-?), founder of the Moroccan Geologic Survey.

Name Pronunciation:

Despujolsite + Pronunciation

Synonym:

ICSD 15729

PDF 20-226

Despujolsite Crystallography

Axial Ratios:

a:c = 1:1.257

Cell Dimensions:

a = 8.56, c = 10.76, Z = 2; V = 682.80 Den(Calc)= 2.55

Crystal System:

Hexagonal - Ditrigonal Dipyramidal H-M Symbol (6 m2) Space Group: P 62c

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

By Intensity(I/I_o): 3.34(1), 2.129(0.8), 4.26(0.8),

Physical Properties of Despujolsite

Cleavage:

{???} Good

Color:

Lemon.

Density:

2.46

Diaphaneity:

Transparent to Translucent

Fracture:

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

Hardness:

2.5 - Finger Nail

Luster:

Vitreous (Glassy)

Optical Properties of Despujolsite

Gladstone-Dale:

CI meas= -0.057 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= -0.02 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2624,KPDmeas= 0.272,KC= 0.2573
Ncalc = 1.63 - 1.66

Optical Data:

Uniaxial (+), w=1.656, e=1.682, bire=0.0260.

Calculated Properties of Despujolsite

Electron Density:

Bulk Density (Electron Density)=2.58 gm/cc
note: Specific Gravity of Despujolsite =2.55 gm/cc.

Fermion Index:

Fermion Index = 0.0014820241
Boson Index = 0.9985179759

Photoelectric:

PE_Despujolsite= 6.16 barns/electron
U=PE_Despujolsite x rElectron Density= 15.90 barns/cc.

Radioactivity:

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

Despujolsite Classification

Dana Class:

31.07.06.01 (31)Hydrated Sulfates Containing Hydroxyl or Halogen

(31.07)where (A+ B++)2 (XO4) Zqï¿½x(H2O)

(31.07.06)Despujolsite Group

31.07.06.01 Despujolsite Ca3Mn(SO4)2(OH)6•3(H2O) P 62c 6 m2

31.07.06.02 Schaurteite Ca3Ge(SO4)2(OH)6•3(H2O) P 62c 6 m2

31.07.06.03 Fleischerite Pb3Ge(SO4)2(OH)6•3(H2O) P 6₃/mmc 6/m 2/m 2/m

31.07.06.04 Mallestigite! Pb3Sb(SO4)(AsO4)(OH)6•3(H2O) P 6₃ 6 2 2

Strunz Class:

07.DF.25 07 - SULFATES (SELENATES, TELLURATES)

07.D - Sulfates (selenates, etc.) with additional anions, with H2O

07.DF -With large and medium-sized cations

07.DF.25 Despujolsite Ca3Mn(SO4)2(OH)6•3(H2O) P 62c 6 m2

07.DF.25 Fleischerite Pb3Ge(SO4)2(OH)6•3(H2O) P 6₃/mmc 6/m 2/m 2/m

07.DF.25 Mallestigite! Pb3Sb(SO4)(AsO4)(OH)6•3(H2O) P 6₃ 6 2 2

07.DF.25 Schaurteite Ca3Ge(SO4)2(OH)6•3(H2O) P 62c 6 m2

Other Despujolsite Information

References:

NAME( AntBidBlaNic5) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Despujolsite :
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 Despujolsite Specimen Label here :

Despujolsite

Ca3Mn++++(SO4)2(OH)6•3(H2O)
Dana No: 31.07.06.01 Strunz No: 07.DF.25
Locality:

Notes:

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