Orpheite Mineral Data

General Orpheite Information

Chemical Formula:

PbAl3(PO4,SO4)2(OH)6 (?)

Composition:

Molecular Weight = 580.68 gm

Aluminum 13.94 % Al 26.34 % Al₂O₃

Phosphorus 8.00 % P 18.33 % P₂O₅

Hydrogen 1.04 % H 9.31 % H₂O

Lead 35.68 % Pb 38.44 % PbO

Sulfur 2.76 % S 6.89 % SO₃

Oxygen 38.57 % O

______ ______

100.00 % 99.31 % = TOTAL OXIDE

Empirical Formula:

PbAl₃(PO₄)_1.5(SO₄)_0.5(OH)₆

Environment:

Secondary mineral in the oxidized zone of a polymetallic deposit.

IMA Status:

Approved IMA 1971

Locality:

Madjarovo Pb-Zn deposit, eastern Rhodopes Mountains, 60 km southeast of Haskovo, Bulgaria. Link to MinDat.org Location Data.

Name Origin:

Named for Orpheus, mythical singer in the Rhodopes Mountains.

Name Pronunciation:

Orpheite

Orpheite Image

Images:

Orpheite

Comments: Opaque botryoidal orpheite crust.
Location: Near Valmy, Humboldt County, Nevada, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Orpheite Crystallography

Axial Ratios:

a:c = 1:2.38857

Cell Dimensions:

a = 7, c = 16.72, Z = 3; V = 709.52 Den(Calc)= 4.08

Crystal System:

Trigonal - Hexagonal Scalenohedral H-M Symbol (3 2/m) Space Group: R 3m

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

By Intensity(I/I_o): 5.66(1), 2.96(0.95), 3.5(0.65),

Physical Properties of Orpheite

Color:

Colorless, Gray, Gray blue, Yellow green, Light blue.

Density:

3.75

Diaphaneity:

Transparent to Translucent

Hardness:

3.5 - Copper Penny

Luminescence:

Fluorescent, Short UV=turquoise blue, Long UV=turquoise blue.

Streak:

white

Optical Properties of Orpheite

Dichroism (e):

colorless.

Dichroism (w):

colorless.

Gladstone-Dale:

CI meas= 0.009 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.089 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1668,KPDmeas= 0.1815,KC= 0.183
Ncalc = 1.69 - 1.75

Optical Data:

Uniaxial (+), w=1.67, e=1.691, bire=0.0210.

Calculated Properties of Orpheite

Electron Density:

Bulk Density (Electron Density)=3.48 gm/cc
note: Specific Gravity of Orpheite =3.75 gm/cc.

Fermion Index:

Fermion Index = 0.07
Boson Index = 0.93

Photoelectric:

PE_Orpheite= 591.17 barns/electron
U=PE_Orpheite x rElectron Density=2,057.78 barns/cc.

Radioactivity:

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

Orpheite Classification

Dana Class:

43.04.01.04 (43)Compound Phosphates, etc.

(43.04)(Anhydrous Compound Anions With Hydroxyl or Halogen)

(43.04.01)Beudantite Group

43.04.01.01 Beudantite PbFe3(AsO4)(SO4)(OH)6 R 3m 3 2/m

43.04.01.02 Corkite PbFe3(PO4)(SO4)(OH)6 R 3m 3m

43.04.01.03 Hidalgoite PbAl3(AsO4)(SO4)(OH)6 R 3m 3 2/m

43.04.01.04 Orpheite PbAl3(PO4,SO4)2(OH)6(?) R 3m 3 2/m

43.04.01.05 Hinsdalite (Pb,Sr)Al3(PO4)(SO4)(OH)6 R 3m 3 2/m

43.04.01.06 Svanbergite SrAl3(PO4)(SO4)(OH)6 R 3m 3 2/m

43.04.01.07 Kemmlitzite (Sr,Ce)Al3(AsO4)(SO4)(OH)6 R 3m 3 2/m

43.04.01.08 Woodhouseite CaAl3(PO4)(SO4)(OH)6 R 3m 3 2/m

43.04.01.09 Weilerite BaAl3H[(As,P)O4]2(OH)6 R 3m 3 2/m

43.04.01.10 Gallobeudantite! PbGa3[(AsO4),(SO4)]2(OH)6 R 3m 3m

Strunz Class:

08.BL.05 08 - PHOSPHATES, ARSENATES, VANADATES

08.B - Phosphates, etc. with Additional Anions, without H2O

08.BL -With medium-sized and large cations, (OH, etc.):RO4 = 3:1

08.BL.05 Beudantite PbFe3(AsO4)(SO4)(OH)6 R 3m 3 2/m

08.BL.05 Corkite PbFe3(PO4)(SO4)(OH)6 R 3m 3m

08.BL.05 Hidalgoite PbAl3(AsO4)(SO4)(OH)6 R 3m 3 2/m

08.BL.05 Gallobeudantite! PbGa3[(AsO4),(SO4)]2(OH)6 R 3m 3m

08.BL.05 Hinsdalite (Pb,Sr)Al3(PO4)(SO4)(OH)6 R 3m 3 2/m

08.BL.05 Kemmlitzite (Sr,Ce)Al3(AsO4)(SO4)(OH)6 R 3m 3 2/m

08.BL.05 Orpheite PbAl3(PO4,SO4)2(OH)6(?) R 3m 3 2/m

08.BL.05 Woodhouseite CaAl3(PO4)(SO4)(OH)6 R 3m 3 2/m

08.BL.05 Weilerite BaAl3H[(As,P)O4]2(OH)6 R 3m 3 2/m

08.BL.05 Svanbergite SrAl3(PO4)(SO4)(OH)6 R 3m 3 2/m

Other Orpheite 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 Orpheite :
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

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

Orpheite

PbAl3(PO4,SO4)2(OH)6 (?)
Dana No: 43.04.01.04 Strunz No: 08.BL.05
Locality:

Notes:

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