Bergenite
A valid IMA mineral species - grandfathered
This page is currently not sponsored. Click here to sponsor this page.
About Bergenite
Formula:
Ca2Ba4(UO2)9(PO4)6O6 · 16H2O
Colour:
Yellow
Specific Gravity:
4.82 (Calculated)
Crystal System:
Monoclinic
Member of:
Name:
Named in 1959 by Hans Wilhelm Bültemann and Gunter Harald Moh for the region near type locality Bergen, Saxony, Germany. The artificial compound was synthesized in 1956 by V. Ross and was called barium-phosphuranylite.
Type Locality:
This page provides mineralogical data about Bergenite.
Unique Identifiers
Mindat ID:
631
Long-form identifier:
mindat:1:1:631:0
Classification of Bergenite
Phosphuranylite sheet topology
The sheet topology exhibited by members of the phosphuranylite group.
IMA Classification of Bergenite
Approved, 'Grandfathered' (first described prior to 1959)
IMA Formula:
Ca2Ba4(U6+O2)9O6(PO4)6·16H2O
First published:
1959
Type description reference:
8.EC.40
8 : PHOSPHATES, ARSENATES, VANADATES
E : Uranyl phosphates and arsenates
C : UO2:RO4 = 3:2
8 : PHOSPHATES, ARSENATES, VANADATES
E : Uranyl phosphates and arsenates
C : UO2:RO4 = 3:2
42.4.5.3
42 : HYDRATED PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
4 : (AB)5(XO4)2Zq·xH2O
42 : HYDRATED PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
4 : (AB)5(XO4)2Zq·xH2O
19.11.20
19 : Phosphates
11 : Phosphates of U
19 : Phosphates
11 : Phosphates of 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 |
|---|---|---|
| Bgn | 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 Bergenite
Transparency:
Translucent
Colour:
Yellow
Streak:
Pale yellow
Density:
4.82 g/cm3 (Calculated)
Optical Data of Bergenite
Type:
Biaxial (-)
RI values:
nα = 1.66 nβ = 1.7 - 1.71 nγ = 1.722
Max. Birefringence:
δ = 0.062
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.
No measured or calculated 2V is on file for this mineral, so the value used here (62°) is estimated from its recorded refractive indices and optic sign, not from a direct 2V measurement.
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.
No measured or calculated 2V is on file for this mineral, so the value used here (62°) is estimated from its recorded refractive indices and optic sign, not from a direct 2V measurement.
Dispersion:
weak
Chemistry of Bergenite
Mindat Formula:
Ca2Ba4(UO2)9(PO4)6O6 · 16H2O
Element Weights:
Crystallography of Bergenite
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/b
Cell Parameters:
a = 10.092 Å, b = 17.245 Å, c = 17.355 Å
β = 113.678°
β = 113.678°
Ratio:
a:b:c = 0.585 : 1 : 1.006
Unit Cell V:
2766.2 ų
Z:
2
Morphology:
Thin tabular.
Comment:
Data from Locock and Burns (2003)
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) |
|---|---|---|---|---|---|---|---|
| 0005828 | Bergenite | Locock A J, Burns P C (2003) The crystal structure of bergenite, a new geometrical isomer of the phosphuranylite group The Canadian Mineralogist 41 91-101 |  | 2003 | 0 | 293 |
CIF Raw Data - click here to close
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 7.73 Å | (100) |
| 3.837 Å | (80) |
| 3.054 Å | (60) |
| 2.874 Å | (50) |
| 2.826 Å | (50) |
| 8.54 Å | (40) |
| 3.742 Å | (40) |
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 Bergenite
Place of Conservation of Type Material:
No designated type material.
Associated Minerals at Type Locality:
Synonyms of Bergenite
Other Language Names for Bergenite
Relationship of Bergenite to other Species
Member of:
Other Members of Phosphuranylite Group:
| Althupite | AlTh(UO2)7(PO4)4(OH)5O2 · 15H2O | Tric. 1 : P1 |
| Dewindtite | H2Pb3(UO2)6O4(PO4)4 · 12H2O | Orth. mmm(2/m2/m2/m) : Cmma |
| Dumontite | Pb2(UO2)3O2(PO4)2 · 5H2O | Mon. 2/m : P21/m |
| Françoisite-(Ce) | (Ce,Nd,Ca)(UO2)3(PO4)2O(OH) · 6H2O | Mon. 2/m : P21/b |
| Françoisite-(Nd) | (Nd,Ce,Sm)(UO2)3(PO4)2O(OH) · 6H2O | Mon. 2/m |
| Hügelite | Pb2(UO2)3(AsO4)2O2 · 5H2O | Mon. 2/m : P21/m |
| Phosphuranylite | KCa(H3O)3(UO2)7(PO4)4O4 · 8H2O | Orth. mmm(2/m2/m2/m) : Cmcm |
| Phuralumite | Al2[(UO2)3(PO4)2O(OH)](OH)3(H2O)9 | Mon. 2/m |
| Phurcalite | Ca2(UO2)3(PO4)2O2 · 7H2O | Orth. mmm(2/m2/m2/m) : Pbca |
| Upalite | Al(UO2)3(PO4)2O(OH) · 7H2O | Mon. 2/m : P21/b |
| Vanmeersscheite | U6+(UO2)3(PO4)2(OH)6 · 4H2O | Orth. mmm(2/m2/m2/m) |
| Yingjiangite | K2Ca(UO2)7(PO4)4(OH)6 · 6H2O | Orth. mmm(2/m2/m2/m) : Cmcm |
Common Associates
Associations Based on Photo Data:
Related Minerals - Strunz-mindat Grouping
| 8.EC.05 | Upalite | Al(UO2)3(PO4)2O(OH) · 7H2O |
| 8.EC.05 | Françoisite-(Nd) | (Nd,Ce,Sm)(UO2)3(PO4)2O(OH) · 6H2O |
| 8.EC.05 | Françoisite-(Ce) | (Ce,Nd,Ca)(UO2)3(PO4)2O(OH) · 6H2O |
| 8.EC.05 | Phuralumite | Al2[(UO2)3(PO4)2O(OH)](OH)3(H2O)9 |
| 8.EC.10 | Yingjiangite | K2Ca(UO2)7(PO4)4(OH)6 · 6H2O |
| 8.EC.10 | Renardite | Pb(UO2)4(PO4)2(OH)4 · H2O |
| 8.EC.10 | Phosphuranylite | KCa(H3O)3(UO2)7(PO4)4O4 · 8H2O |
| 8.EC.10 | Arsenuranylite | Ca(UO2)4(AsO4)2(OH)4 · 6H2O |
| 8.EC.10 | 'Kivuite' | Th(UO2)4(PO3OH)2(OH)8 · 7H2O |
| 8.EC.10 | Dewindtite | H2Pb3(UO2)6O4(PO4)4 · 12H2O |
| 8.EC.15 | Dumontite | Pb2(UO2)3O2(PO4)2 · 5H2O |
| 8.EC.15 | Hügelite | Pb2(UO2)3(AsO4)2O2 · 5H2O |
| 8.EC.20 | Vanmeersscheite | U6+(UO2)3(PO4)2(OH)6 · 4H2O |
| 8.EC.20 | Arsenovanmeersscheite | U6+(UO2)3(AsO4)2(OH)6 · 4H2O |
| 8.EC.20 | Metavanmeersscheite | U6+(UO2)3(PO4)2(OH)6 · 2H2O |
| 8.EC.25 | Althupite | AlTh(UO2)7(PO4)4(OH)5O2 · 15H2O |
| 8.EC.30 | Mundite | Al(UO2)3(PO4)2(OH)3 · 5.5H2O |
| 8.EC.35 | Phurcalite | Ca2(UO2)3(PO4)2O2 · 7H2O |
Radioactivity
Radioactivity:
| Element | % Content | Activity (Bq/kg) | Radiation Type |
|---|---|---|---|
| Uranium (U) | 53.3726% | 13,343,150 | 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 Bergenite
Weak orange-brown in short- and long-wave ultraviolet light.
Other Information
Notes:
Radioactive
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Internet Links for Bergenite
mindat.org URL:
https://www.mindat.org/min-631.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
Mineral Dealers:
References for Bergenite
Reference List:
Ross, Virginia (1956) Studies of uranium minerals (XXII): Synthetic calcium and lead uranyl phosphate minerals. American Mineralogist, 41 (11-12) 915-926
Cabri, Louis J., Fleischer, Michael, Pabst, Adolf (1981) New Mineral Names. American Mineralogist, 66 (9-10) 1099-1103 p.1102
Locock, A. J., Burns, P. C. (2003) The Crystal Structure of Bergenite, a New Geometrical Isomer of the Phosphuranylite Group. The Canadian Mineralogist, 41 (1). 91-101 doi:10.2113/gscanmin.41.1.91
Burns, Peter C. (2005) U6+ minerals and inorganic compounds: insights into an expanded structural hierarchy of crystal structures. The Canadian Mineralogist, 43 (6) 1839-1894 doi:10.2113/gscanmin.43.6.1839
Localities for Bergenite
Showing 9 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.
France | |
| Kolitsch et al. (2009) |
Germany | |
| Hochleitner (1982) |
| Wittern (2001) |
| Hajek (2010) |
| Bültemann et al. (1959) |
| Tröger (2006) +1 other reference |
| "Sigurd Stordal" Collection (E-Rocks) |
| Wittern (2001) | |
USA | |
| Min News 13:7 p2 |
Quick NavTopAbout BergeniteUnique IdentifiersClassification IMA Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography Crystal StructureX-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesRelationshipsCommon AssociatesStrunz-MindatRadioactivityFluorescence Other InformationInternet Links References Localities Locality List
Streuberg Quarry, Bergen, Vogtlandkreis, Saxony, Germany