Log In
Pseudograndreefite
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Pseudograndreefite
Formula:
Pb6(SO4)F10
Colour:
Colourless
Lustre:
Sub-Adamantine
Hardness:
2½
Specific Gravity:
7.0
Crystal System:
Orthorhombic
Name:
For the close resemblance to grandreefite.
A rare secondary lead sulphate fluoride.
The lower indices of refraction, larger 2V, and stronger dispersion are useful in distinguishing pseudograndreefite from grandreefite.
The lower indices of refraction, larger 2V, and stronger dispersion are useful in distinguishing pseudograndreefite from grandreefite.
Unique Identifiers
Mindat ID:
3298
Long-form identifier:
mindat:1:1:3298:4
IMA Classification of Pseudograndreefite
Approved
IMA Formula:
Pb2+6(S6+O4)F10
Approval year:
1988
First published:
1989
Classification of Pseudograndreefite
7.BD.65
7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
B : Sulfates (selenates, etc.) with additional anions, without H2O
D : With only large cations
7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
B : Sulfates (selenates, etc.) with additional anions, without H2O
D : With only large cations
12.1.3.1
12 : COMPOUND HALIDES
1 : Miscellaneous
12 : COMPOUND HALIDES
1 : Miscellaneous
26.23
26 : Sulphates with Halide
26 : Sulphates with Halide
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 |
|---|---|---|
| Pgrf | 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 Pseudograndreefite
Sub-Adamantine
Transparency:
Transparent
Colour:
Colourless
Streak:
White
Hardness:
2½ on Mohs scale
Tenacity:
Brittle
Cleavage:
None Observed
Fracture:
Conchoidal
Density:
7.0(1) g/cm3 (Measured) 7.08 g/cm3 (Calculated)
Optical Data of Pseudograndreefite
Type:
Biaxial (+)
RI values:
nα = 1.864 nβ = 1.865 nγ = 1.873
2V:
Measured: 30° , Calculated: 40°
Max. Birefringence:
δ = 0.009
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
Optical Extinction:
X = c; Y = a; Z = b.
Chemistry of Pseudograndreefite
Mindat Formula:
Pb6(SO4)F10
Element Weights:
Elements listed:
Crystallography of Pseudograndreefite
Crystal System:
Orthorhombic
Class (H-M):
222 - Disphenoidal
Space Group:
F222
Setting:
F222
Cell Parameters:
a = 8.51 Å, b = 19.57 Å, c = 8.49 Å
Ratio:
a:b:c = 0.435 : 1 : 0.434
Unit Cell V:
1,413.93 ų (Calculated from Unit Cell)
Z:
4
Morphology:
Tabular on {010}. Forms include {010}, {100}, {001}, {2l0}, and {012}.
Twinning:
None observed.
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 3.204 Å | (100) |
| 1.779 Å | (70b) |
| 2.999 Å | (30) |
| 2.212 Å | (25) |
| 1.364 Å | (25b) |
| 3.89 Å | (20) |
| 2.123 Å | (20) |
Reference:
Comments:
Grand Reef mine, Arizona, USA. Data from the type description.
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Stage 7: Great Oxidation Event | <2.4 |
| 47b : [Sulfates and sulfites] | |
| 47g : [Halogen-bearing surface weathering minerals] |
Type Occurrence of Pseudograndreefite
General Appearance of Type Material:
Square (pseudotetragonal) tabular crystals. The tablets form a subparallel aggregate measuring 4x1x4 mm.
Place of Conservation of Type Material:
Natural History Museum, Los Angeles, California, USA, 33608.
National Museum of Natural History (Smithsonian), Washington, D.C., USA, 166056.
National Museum of Natural History (Smithsonian), Washington, D.C., USA, 166056.
Geological Setting of Type Material:
Epithermal lead-copper-silver deposit, which is hosted by a silicified breccia.
Associated Minerals at Type Locality:
Synonyms of Pseudograndreefite
Other Language Names for Pseudograndreefite
Common Associates
Associations Based on Photo Data:
| 1 photo of Pseudograndreefite associated with Grandreefite | Pb2(SO4)F2 |
Related Minerals - Strunz-mindat Grouping
| 7.BD. | Hasanovite | KNa(MoO2)(SO4)2 |
| 7.BD. | Kennygayite | [Pb4O2(OH)2](SO4) |
| 7.BD. | Adanite | Pb2(Te4+O3)(SO4) |
| 7.BD. | Cadsulfohite | Cd2(SO4)(OH)2 |
| 7.BD. | Hyblerite | Pb4Bi2(SO4)2(CO3)O4 |
| 7.BD. | Zanelliite | PbCu9[AsO3.5(OH)0.5]2(AsO4)2(OH)9(H2O)3 |
| 7.BD. | Evanichite | Pb6Cr3+(Cr6+O4)2(SO4)(OH)7FCl |
| 7.BD.05 | Sulphohalite | Na6(SO4)2FCl |
| 7.BD.10 | Galeite | Na15(SO4)5F4Cl |
| 7.BD.10 | Schairerite | Na21(SO4)7ClF6 |
| 7.BD.15 | Kogarkoite | Na3(SO4)F |
| 7.BD.20 | Aiolosite | Na4Bi(SO4)3Cl |
| 7.BD.20 | Caracolite | Na3Pb2(SO4)3Cl |
| 7.BD.20 | Cesanite | Na3Ca2(SO4)3(OH) |
| 7.BD.25 | Burkeite | Na6(CO3)(SO4)2 |
| 7.BD.30 | Hanksite | Na22K(SO4)9(CO3)2Cl |
| 7.BD.35 | Cannonite | Bi2(SO4)O(OH)2 |
| 7.BD.40 | Lanarkite | Pb2(SO4)O |
| 7.BD.45 | Grandreefite | Pb2(SO4)F2 |
| 7.BD.50 | Itoite | Pb3Ge4+(SO4)2O2(OH)2 |
| 7.BD.55 | Chiluite | Bi3Te6+Mo6+O10.5 |
| 7.BD.60 | Hectorfloresite | Na9(SO4)4(IO3) |
| 7.BD.70 | Sundiusite | Pb10(SO4)O8Cl2 |
Fluorescence of Pseudograndreefite
Not fluorescent
Other Information
Notes:
Decomposes in cold water.
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 Pseudograndreefite
mindat.org URL:
https://www.mindat.org/min-3298.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 Pseudograndreefite
Localities for Pseudograndreefite
Showing 1 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.
USA (TL) | |
| Kampf et al. (1989) +2 other references |
Quick NavTopAbout PseudograndreefiteUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesCommon AssociatesStrunz-MindatFluorescence Other InformationInternet Links References Localities Locality List
Grand Reef Mine, Laurel Canyon, Grand Reef Mountain, Klondyke, Aravaipa Mining District, Graham County, Arizona, USA