Widenmannite
A valid IMA mineral species
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About Widenmannite
Formula:
Pb2(OH)2[(UO2)(CO3)2]
Originally assumed to be Pb2(UO2)(CO3)3.
Colour:
Yellow, very pale greenish yellow, colorless
Lustre:
Silky, Pearly
Hardness:
2
Specific Gravity:
6.89 (Calculated)
Crystal System:
Orthorhombic
Name:
Named after Johann Friedrich Wilhelm Widenmann (5 February 1764, Kirchheim unter Teck, Kingdom of Prussia - 13 March 1798, Michelstadt, Kingdom of Prussia), German mining official ('Württembergischer Bergrat') who, in 1793, first reported on the occurrence of a uranium mica in the Black Forest.
This page provides mineralogical data about Widenmannite.
Unique Identifiers
Mindat ID:
4285
Long-form identifier:
mindat:1:1:4285:3
IMA Classification of Widenmannite
Approved
IMA Formula:
Pb2+2U6+O2(CO3)2(OH)2
Approval year:
1974
First published:
1976
Classification of Widenmannite
5.ED.40
5 : CARBONATES (NITRATES)
E : Uranyl Carbonates
D : UO2:CO3 = 1:3
5 : CARBONATES (NITRATES)
E : Uranyl Carbonates
D : UO2:CO3 = 1:3
14.1.5.1
14 : ANHYDROUS NORMAL CARBONATES
1 : A(XO3)
14 : ANHYDROUS NORMAL CARBONATES
1 : A(XO3)
11.11.19
11 : Carbonates
11 : Carbonates of Cr and U
11 : Carbonates
11 : Carbonates of Cr and U
Mineral Symbols
As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Wdm | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Widenmannite
Silky, Pearly
Transparency:
Transparent, Translucent
Colour:
Yellow, very pale greenish yellow, colorless
Streak:
Pale yellow
Hardness:
2 on Mohs scale
Cleavage:
Perfect
on {010}
on {010}
Density:
6.89 g/cm3 (Calculated)
Optical Data of Widenmannite
Type:
Biaxial (-)
RI values:
nα = 1.803(5) nβ = 1.905(5) nγ = 1.945(5)
2V:
Measured: 63° , Calculated: 60°
Max. Birefringence:
δ = 0.142
Based on recorded range of RI values above.
Based on recorded range of RI values above.
Interference Colours:
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.
Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.
Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.
Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.
Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
Surface Relief:
Very High (positive)
Relative to Canada balsam mounting medium (n ≈ 1.537).
Relative to Canada balsam mounting medium (n ≈ 1.537).
This shows the grain boundary and Becke line effect under plane-polarised
light, based on the contrast between this mineral's average refractive
index and the mounting medium. It does not take into account mineral
colouration.
In focus
Interference Figure:
This shows the idealized biaxial acute bisectrix (Bxa) interference figure
- the conoscopic view for a grain cut perpendicular to the acute bisectrix, using
this mineral's 2V. The two small white dots mark the melatopes - the points
where the two optic axes emerge - and are shown only when they fall within the
field of view. The coloured bands are isochromatics, and the dark bands are
isogyres.
Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.
Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.
Dispersion:
r > v extreme
Chemistry of Widenmannite
Mindat Formula:
Pb2(OH)2[(UO2)(CO3)2]
Originally assumed to be Pb2(UO2)(CO3)3.
Originally assumed to be Pb2(UO2)(CO3)3.
Element Weights:
Crystallography of Widenmannite
Crystal System:
Orthorhombic
Class (H-M):
mmm(2/m2/m2/m) - Dipyramidal
Space Group:
Pmmn
Cell Parameters:
a = 4.9744(9) Å, b = 9.3816(16) Å, c = 8.9539(15) Å
Ratio:
a:b:c = 0.53 : 1 : 0.954
Unit Cell V:
417.86 ų
Z:
2
Morphology:
Lath-like crystals in tufts and mats.
Comment:
Data from Plášil et al. (2014).
Crystal Structure
Load
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Show
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Display Options
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
View
CIF File Best | x | y | z | a | b | c
CIF File Best | x | y | z | a | b | c
Rotation
Stop | Start
Stop | Start
Labels
Console Off | On | Grey | Yellow
Console Off | On | Grey | Yellow
Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure
| ID | Species | Reference | Link | Year | Locality | Pressure (GPa) | Temp (K) |
|---|---|---|---|---|---|---|---|
| 0020040 | Widenmannite | Plasil J, Palatinus L, Rohlicek J, Houdkovaq L, Klementova M, Golias V, Skacha P (2014) Crystal structure of lead uranyl carbonate mineral widenmannite: Precession electron-diffraction and synchrotron powder-diffraction study American Mineralogist 99 276-282 | 2014 | Brezove Hory deposit, Pribram ore district, Czech Republic | 0 | 293 | |
| 0020039 | Widenmannite | Plasil J, Palatinus L, Rohlicek J, Houdkovaq L, Klementova M, Golias V, Skacha P (2014) Crystal structure of lead uranyl carbonate mineral widenmannite: Precession electron-diffraction and synchrotron powder-diffraction study American Mineralogist 99 276-282 | 2014 | Brezove Hory deposit, Pribram ore district, Czech Republic | 0 | 293 |
CIF Raw Data - click here to close
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 4.16 Å | (100) |
| 2.34 Å | (100) |
| 3.19 Å | (80b) |
| 3.34 Å | (70) |
| 1.911 Å | (50) |
| 1.869 Å | (50) |
| 1.473 Å | (50b) |
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Stage 7: Great Oxidation Event | <2.4 |
| 47a : [Near-surface hydration of prior minerals] | |
| 47c : [Carbonates, phosphates, borates, nitrates] | |
| 47f : [Uranyl (U⁶⁺) minerals] |
Type Occurrence of Widenmannite
Place of Conservation of Type Material:
[University of Strassburg, Strassburg, France.]
Geological Setting of Type Material:
Oxidation zone hydrothermal As-Pb deposit
Associated Minerals at Type Locality:
Synonyms of Widenmannite
Other Language Names for Widenmannite
Common Associates
Associations Based on Photo Data:
| 3 photos of Widenmannite associated with Kasolite | Pb(UO2)(SiO4) · H2O |
| 3 photos of Widenmannite associated with Cerussite | PbCO3 |
| 3 photos of Widenmannite associated with Hügelite | Pb2(UO2)3(AsO4)2O2 · 5H2O |
| 1 photo of Widenmannite associated with Erythrite | Co3(AsO4)2 · 8H2O |
| 1 photo of Widenmannite associated with Sklodowskite | Mg(UO2)2(SiO3OH)2 · 6H2O |
| 1 photo of Widenmannite associated with Torbernite | Cu(UO2)2(PO4)2 · 12H2O |
| 1 photo of Widenmannite associated with Quartz | SiO2 |
| 1 photo of Widenmannite associated with Goethite | Fe3+O(OH) |
Related Minerals - Strunz-mindat Grouping
| 5.ED. | Szilagyiite | NaCa3(UO2)(CO3)3(SeO3)F(H2O)6 |
| 5.ED. | Pendevilleite-(Y) | Mg2Y3Al(UO2)2(CO3)7(OH)6(H2O)16 |
| 5.ED. | Paramarkeyite | Ca2(UO2)(CO3)3 · 5H2O |
| 5.ED.05 | Bayleyite | Mg2(UO2)(CO3)3 · 18H2O |
| 5.ED.10 | Swartzite | MgCa(UO2)(CO3)3 · 12H2O |
| 5.ED.15 | Albrechtschraufite | Ca4Mg(UO2)2(CO3)6F2 · 17-18H2O |
| 5.ED.20 | Liebigite | Ca2(UO2)(CO3)3 · 11H2O |
| 5.ED.25 | Rabbittite | Ca3Mg3(UO2)2(CO3)6(OH)4 · 18H2O |
| 5.ED.30 | Andersonite | Na2Ca(UO2)(CO3)3 · 5.33H2O |
| 5.ED.35 | Grimselite | K3Na(UO2)(CO3)3 · H2O |
| 5.ED.45 | Znucalite | Zn10Ca0.83(UO2)0.83(CO3)4(OH)15.31(H2O)5.48 |
| 5.ED.50 | Agricolaite | K4(UO2)(CO3)3 |
| 5.ED.50 | Čejkaite | Na4(UO2)(CO3)3 |
| 5.ED.55 | Línekite | K2Ca3[(UO2)(CO3)3]2 · 8H2O |
| 5.ED.55 | Braunerite | K2Ca(UO2)(CO3)3 · 6H2O |
| 5.ED.60 | Leószilárdite | Na6Mg(UO2)2(CO3)6 · 6H2O |
| 5.ED.65 | Pseudomarkeyite | Ca8(UO2)4(CO3)12 · 21H2O |
| 5.ED.65 | Natromarkeyite | Na2Ca8(UO2)4(CO3)13 · 27H2O |
| 5.ED.65 | Markeyite | Ca9(UO2)4(CO3)13 · 28H2O |
| 5.ED.70 | Paddlewheelite | MgCa5Cu2(UO2)4(CO3)12(H2O)33 |
Radioactivity
Radioactivity:
| Element | % Content | Activity (Bq/kg) | Radiation Type |
|---|---|---|---|
| Uranium (U) | 28.3888% | 7,097,200 | α, β, γ |
| Thorium (Th) | 0.0000% | 0 | α, β, γ |
| Potassium (K) | 0.0000% | 0 | β, γ |
For comparison:
- Banana: ~15 Bq per fruit
- Granite: 1,000–3,000 Bq/kg
- EU exemption limit: 10,000 Bq/kg
Note: Risk is shown relative to daily recommended maximum exposure to non-background radiation of 1000 µSv/year. Note that natural background radiation averages around 2400 µSv/year so in reality these risks are probably extremely overstated! With infrequent handling and safe storage natural radioactive minerals do not usually pose much risk.
Interactive Simulator:
Note: The mass selector refers to the mass of radioactive mineral present, not the full specimen, also be aware that the matrix may also be radioactive, possibly more radioactive than this mineral!
Activity: –
| Distance | Dose rate | Risk |
|---|---|---|
| 1 cm | ||
| 10 cm | ||
| 1 m |
The external dose rate (D) from a radioactive mineral is estimated by summing the gamma radiation contributions from its Uranium, Thorium, and Potassium content, disregarding daughter-product which may have a significant effect in some cases (eg 'pitchblende'). This involves multiplying the activity (A, in Bq) of each element by its specific gamma ray constant (Γ), which accounts for its unique gamma emissions. The total unshielded dose at 1 cm is then scaled by the square of the distance (r, in cm) and multiplied by a shielding factor (μshield). This calculation provides a 'worst-case' or 'maximum risk' estimate because it assumes the sample is a point source and entirely neglects any self-shielding where radiation is absorbed within the mineral itself, meaning actual doses will typically be lower. The resulting dose rate (D) is expressed in microsieverts per hour (μSv/h).
D = ((AU × ΓU) + (ATh × ΓTh) + (AK × ΓK)) / r2 × μshield
Fluorescence of Widenmannite
Non-fluorescent.
Other Information
Health Risks:
Radioactive
Internet Links for Widenmannite
mindat.org URL:
https://www.mindat.org/min-4285.html
Please feel free to link to this page.
Please feel free to link to this page.
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External Links:
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References for Widenmannite
Reference List:
Elton, N. J., Hooper, J. J. (1995) Widenmannite from Cornwall, England: the second world occurrence. Mineralogical Magazine, 59 (397) 745-749 doi:10.1180/minmag.1995.059.397.15
Plášil, J., Čejka, J., Sejkora, J., Škácha, P., Goliáš, V., Jarka, P., Laufek, F., Jehlička, J., Němec, I., Strnad, L. (2010) Widenmannite, a rare uranyl lead carbonate: occurrence, formation and characterization. Mineralogical Magazine, 74 (1) 97-110 doi:10.1180/minmag.2010.074.1.97
Plasil, J.; Palatinus, L.; Rohlicek, J.; Houdkova, L.; Klementova, M.; Golias, V.; Skacha, P. (2014) Crystal structure of lead uranyl carbonate mineral widenmannite: Precession electron-diffraction and synchrotron powder-diffraction study. American Mineralogist, 99 (2). 276-282 doi:10.2138/am.2014.4671
Localities for Widenmannite
Showing 13 localities.
symbol to view information about a locality.
The Locality List
- This locality has map coordinates listed.
- This locality has estimated coordinates.
ⓘ - Click for references and further information on this occurrence.
? - Indicates mineral may be doubtful at this locality.
- Good crystals or important locality for species.
- World class for species or very significant.
(TL) - Type Locality for a valid mineral species.
(FRL) - First Recorded Locality for everything else (eg varieties).
All localities listed without proper references should be considered as questionable.
China | |
| Carnegie Museum of Natural History ... |
Czech Republic | |
| Plášil et al. (2010) |
| Bull.N.M.Praha 2002 +1 other reference | |
| Hloušek et al. (2002) |
| Möhn et al. (12/2021) | |
Finland | |
| Halls (2005) |
Germany (TL) | |
| Fleischer (1962) +3 other references |
| Stolze et al. (09/2020) |
Switzerland | |
| Meisser (2012) |
UK | |
| Elton et al. (1995) +1 other reference |
| Day (1999) |
USA | |
| Carlson et al. (2007) |
| Anné (2007) |
Quick NavTopAbout WidenmanniteUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography Crystal StructureX-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesCommon AssociatesStrunz-MindatRadioactivityFluorescence Other InformationInternet Links References Localities Locality List
Shazijiang U deposit, Miaoershan Uranium ore field, Ziyuan Co., Guilin, Guangxi, China