Plumbogummite Mineral Data
General Plumbogummite Information
Chemical Formula:
PbAl3(PO4)2(OH)5•(H2O)
Composition:
Molecular Weight = 581.14 gm
Aluminum 13.93 % Al 26.32 % Al2 O3
Phosphorus 10.66 % P 24.43 % P2 O5
Hydrogen 1.21 % H 10.85 % H2 O
Lead 35.65 % Pb 38.41 % PbO
Oxygen 38.54 % O
______ ______
100.00 % 100.00 % = TOTAL OXIDE
Empirical Formula:
PbAl3 (PO4 )2 (OH)5 •(H2 O)
IMA Status:
Valid Species (Pre-IMA) 1832
Locality:
Link to MinDat.org Location Data.
Name Origin:
Named after its composition: plumbum - "lead" and gummi - "indian rubber."
Name Pronunciation:
Plumbogummite + Pronunciation
Synonym:
Hitchcockite
ICSD 87868
PDF 35-623
Schadeite
Plumbogummite Image
Images:
Plumbogummite Crystallography
Axial Ratios:
a:c = 1:2.39156
Cell Dimensions:
a = 7.018, c = 16.784, Z = 3; V = 715.90 Den(Calc)= 4.04
Crystal System:
Trigonal - Hexagonal Scalenohedral H-M Symbol (3 2/m) Space Group: R 3 m
X Ray Diffraction:
By Intensity(I/Io ): 2.97(1), 5.73(0.8), 3.51(0.6),
Physical Properties of Plumbogummite
Cleavage:
None
Color:
White, Gray, Yellow, Bluish green, Brown.
Density:
4 - 5, Average = 4.5
Diaphaneity:
Translucent
Fracture:
Conchoidal - Uneven - Uneven fracture producing small, conchoidal fragments.
Habit:
Colloform - Forming from a gel or colloidal mass.
Habit:
Stalactitic - Shaped like pendant columns as stalactites or stalagmites (e.g. calcite).
Hardness:
4-5 - Fluorite-Apatite
Luminescence:
Non-fluorescent.
Luster:
Greasy (Oily)
Streak:
white
Optical Properties of Plumbogummite
Dichroism (e):
n.
Gladstone-Dale:
CI meas = 0.212 (Poor) - where the CI = (1-KPDmeas /KC ) CI calc = 0.122 (Poor) - where the CI = (1-KPDcalc /KC )
KPDcalc = 0.1644,KPDmeas = 0.1476,KC = 0.1871 Ncalc = 1.75 - 1.94
Optical Data:
Uniaxial (+), w=1.653, e=1.675, bire=0.0220.
Calculated Properties of Plumbogummite
Electron Density:
Bulk Density (Electron Density)=3.75 gm/cc note: Specific Gravity of Plumbogummite =4.04 gm/cc.
Fermion Index:
Fermion Index = 0.07 Boson Index = 0.93
Photoelectric:
PEPlumbogummite = 590.04 barns/electronU=PEPlumbogummite x r Electron Density=2,215.00 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Plumbogummite is Not Radioactive
Plumbogummite Classification
Dana Class:
42.07.03.05 (42) Hydrated Phosphates, etc., Containing Hydroxyl or Halogen
(42.07) where (AB)5 (XO4)3 Zq � x(H2O)
(42.07.03) Crandallite Group
42.07.03.01 Crandallite CaAl3(PO4)2(OH)5•(H2O) R 3 m 3 2/m
42.07.03.02 Gorceixite BaAl3(PO4)(PO3OH)(OH)6 R 3 m 3 2/m
42.07.03.03 Goyazite SrAl3(PO4)2(OH)5•(H2O) R 3 m 3 2/m
42.07.03.04 Lusungite ? (Sr,Pb)Fe3(PO4)2(OH)5•(H2O) R 3m 3m
42.07.03.05 Plumbogummite PbAl3(PO4)2(OH)5•(H2O) R 3 m 3 2/m
42.07.03.06 Kintoreite PbFe3(PO4)2(OH,H2O)6 R 3 m 3 2/m
42.07.03.07 Benauite ! HSrFe3(PO4)2(OH)6 R 3 m 3 2/m
42.07.03.08 Springcreekite ! BaV3(PO4)2(OH,H2O)6 R 3 m 3 2/m
Strunz Class:
08.BL.10 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.10 Arsenogorceixite ! BaAl3AsO3(OH)(AsO4,PO4)(OH,F)6 R 3 m 3 2/m
08.BL.10 Arsenocrandallite (Ca,Sr)Al3[(As,P)O4]2(OH)5•(H2O) R 3m 3m
08.BL.10 Ferrazite ? (Pb,Ba)3(PO4)2•8(H2O)(?) Tri
08.BL.10 Arsenowaylandite * BiAl3(AsO4)2(OH)6 R 3 m 3 2/m
08.BL.10 Benauite ! HSrFe3(PO4)2(OH)6 R 3 m 3 2/m
08.BL.10 Arsenogoyazite (Sr,Ca,Ba)Al3(AsO4,PO4)2(OH,F)5•(H2O) R 3 m 3 2/m
08.BL.10 Dussertite BaFe3(AsO4)2(OH)5 R 3m 3m
08.BL.10 Crandallite CaAl3(PO4)2(OH)5•(H2O) R 3 m 3 2/m
08.BL.10 Goyazite SrAl3(PO4)2(OH)5•(H2O) R 3 m 3 2/m
08.BL.10 Gorceixite BaAl3(PO4)(PO3OH)(OH)6 R 3 m 3 2/m
08.BL.10 Kintoreite PbFe3(PO4)2(OH,H2O)6 R 3 m 3 2/m
08.BL.10 Lusungite ? (Sr,Pb)Fe3(PO4)2(OH)5•(H2O) R 3m 3m
08.BL.10 Philipsbornite PbAl3(AsO4)2(OH)5•(H2O) R 3m-,R 3m Trig
08.BL.10 Plumbogummite PbAl3(PO4)2(OH)5•(H2O) R 3 m 3 2/m
08.BL.10 Segnitite PbFe3H(AsO4)2(OH)6 R 3 m 3 2/m
08.BL.10 Springcreekite ! BaV3(PO4)2(OH,H2O)6 R 3 m 3 2/m
Other Plumbogummite Information
References:
NAME( Duda&Rejl90) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)
See Also:
Links to other databases for Plumbogummite :
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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Plumbogummite
PbAl3(PO4)2(OH)5•(H2O)
Dana No: 42.07.03.05 Strunz No: 08.BL.10
Locality:
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