Grandreefite
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Grandreefite
View of the Grand Reef looking up Laurel Creek
Grand Reef Mine, Laurel Canyon, Grand Reef Mountain, Klondyke, Aravaipa Mining District, Graham County, Arizona, USA
Grand Reef Mine, Laurel Canyon, Grand Reef Mountain, Klondyke, Aravaipa Mining District, Graham County, Arizona, USA
Formula:
Pb2(SO4)F2
Colour:
Colourless
Lustre:
Sub-Adamantine
Hardness:
2½
Specific Gravity:
7.0
Crystal System:
Monoclinic
Name:
Named by Anthony R. Kampf, Peter J. Dunn, and Eugene E. Foord in 1989 after the type locality of Grand Reef Mine, Arizona.
A rare secondary lead sulphate fluoride.
Structurally related to Unnamed (Ba Thiosulphate Fluoride).
The higher indices of refraction, smaller 2V, and weaker dispersion are useful in distinguishing grandreefite from pseudograndreefite.
Structurally related to Unnamed (Ba Thiosulphate Fluoride).
The higher indices of refraction, smaller 2V, and weaker dispersion are useful in distinguishing grandreefite from pseudograndreefite.
Unique Identifiers
Mindat ID:
1738
Long-form identifier:
mindat:1:1:1738:7
GUID
(UUID V4):
(UUID V4):
1da2515d-879a-45f5-b499-308aa72ddefe
IMA Classification of Grandreefite
Approved
Approval year:
1988
First published:
1989
Classification of Grandreefite
7.BD.45
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
12.1.2.1
12 : COMPOUND HALIDES
1 : Miscellaneous
12 : COMPOUND HALIDES
1 : Miscellaneous
26.22
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 |
---|---|---|
Grf | 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 Grandreefite
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) 7.15 g/cm3 (Calculated)
Comment:
Measured with Berman balance using 3.43 mg of sample.
Optical Data of Grandreefite
Type:
Biaxial (+)
RI values:
nα = 1.872 nβ = 1.873 nγ = 1.897
2V:
Measured: 23° , Calculated: 24°
Max Birefringence:
δ = 0.025
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
and does not take into account mineral colouration.
Surface Relief:
Very High
Dispersion:
very strong
Optical Extinction:
X = c, Y = a, Z = b.
Chemistry of Grandreefite
Mindat Formula:
Pb2(SO4)F2
Elements listed:
Crystallography of Grandreefite
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Cell Parameters:
a = 8.667(1) Å, b = 4.4419(6) Å, c = 14.242(2) Å
β = 107.418(2)°
β = 107.418(2)°
Ratio:
a:b:c = 1.951 : 1 : 3.206
Unit Cell V:
523.15 ų (Calculated from Unit Cell)
Z:
4
Morphology:
Prismatic and striated parallel to [001]. The forms {l20}, {l30}, {293}, {2-93}, and {l01} were present.
Twinning:
Coarse polysynthetic twins of undetermined law observed only in transmitted light under crossed polars.
Comment:
Space group A2/a.
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) |
---|---|---|---|---|---|---|---|
0001350 | Grandreefite | Kampf A R (1991) Grandreefite, Pb2F2SO4: Crystal structure and relationship to the lanthanide oxide sulfates, Ln2O2SO4 American Mineralogist 76 278-282 | 1991 | 0 | 293 |
CIF Raw Data - click here to close
X-Ray Powder Diffraction
Powder Diffraction Data:
d-spacing | Intensity |
---|---|
3.159 Å | (100) |
3.116 Å | (90) |
3.084 Å | (80) |
2.281 Å | (50) |
1.824 Å | (50) |
1.806 Å | (60) |
1.370 Å | (50b) |
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 Grandreefite
General Appearance of Type Material:
Isolated prismatic crystals
Place of Conservation of Type Material:
Natural History Museum, Los Angeles, California, USA, 33608.
National Museum of Natural History, Washington, D.C., USA, 166055.
National Museum of Natural History, Washington, D.C., USA, 166055.
Geological Setting of Type Material:
Epithermal lead-copper-silver deposit, which is hosted by a silicified breccia.
Associated Minerals at Type Locality:
Reference:
Kampf, A.R., Dunn, P.J., Foord, E.E. (1989) Grandreefite, pseudograndreefite, laurelite, and aravaipaite: Four new minerals from the Grandreef mine, Graham Co., AZ. American Mineralogist: 74: 927-933.
Synonyms of Grandreefite
Other Language Names for Grandreefite
Common Associates
Associated Minerals Based on Photo Data:
1 photo of Grandreefite associated with Pseudograndreefite | Pb6(SO4)F10 |
Related Minerals - Strunz-mindat Grouping
7.BD. | Adanite | Pb2(Te4+O3)(SO4) |
7.BD. | Hasanovite | KNa(MoO2)(SO4)2 |
7.BD. | Evanichite | Pb6Cr3+(Cr6+O4)2(SO4)(OH)7FCl |
7.BD. | Kennygayite | [Pb4O2(OH)2](SO4) |
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 | Caracolite | Na3Pb2(SO4)3Cl |
7.BD.20 | Cesanite | Na3Ca2(SO4)3(OH) |
7.BD.20 | Aiolosite | Na4Bi(SO4)3Cl |
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.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.65 | Pseudograndreefite | Pb6(SO4)F10 |
7.BD.70 | Sundiusite | Pb10(SO4)O8Cl2 |
Fluorescence of Grandreefite
None observed.
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 Grandreefite
mindat.org URL:
https://www.mindat.org/min-1738.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 Grandreefite
Localities for Grandreefite
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).
Struck out - Mineral was erroneously reported from this locality.
Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).
All localities listed without proper references should be considered as questionable.
All localities listed without proper references should be considered as questionable.
Greece | |
| Lapis et al. (1999) |
USA (TL) | |
| Min.Rec.: 27: 296. +2 other references |
Quick NavTopAbout GrandreefiteUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography Crystal StructureX-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