Grandaite
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About Grandaite
Formula:
Sr2Al(AsO4)2(OH)
Colour:
Bright orange to salmon to brown colour
Lustre:
Vitreous, Waxy
Specific Gravity:
4.378 (Calculated)
Crystal System:
Monoclinic
Member of:
Name:
Due to its size, Cuneo Province is known in Piedmont by the nickname "Provincia Granda" or, more simply, "la Granda" (i.e., The Large One). The mineral is named after this informal appellation of the province that includes the type locality.
This page provides mineralogical data about Grandaite.
Classification of Grandaite
Approved
Approval Year:
2013
8.BG.05
8.00.
8 : PHOSPHATES, ARSENATES, VANADATES
0 :
0 :
8 : PHOSPHATES, ARSENATES, VANADATES
0 :
0 :
Pronounciation of Grandaite
Pronounciation:
| Play | Recorded by | Country |
|---|---|---|
| Jolyon & Katya Ralph | United Kingdom |
Physical Properties of Grandaite
Vitreous, Waxy
Colour:
Bright orange to salmon to brown colour
Streak:
Reddish brown
Density:
4.378 g/cm3 (Calculated)
Optical Data of Grandaite
Type:
Biaxial (+)
RI values:
nα = 1.726(1) nβ = 1.731(1) nγ = 1.752(1)
Max Birefringence:
δ = 0.026
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:
High
Chemical Properties of Grandaite
Formula:
Sr2Al(AsO4)2(OH)
Crystallography of Grandaite
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/m
Setting:
P21/m
Cell Parameters:
a = 7.5764(5) Å, b = 5.9507(4) Å, c = 8.8050(6) Å
β = 112.551(2)°
β = 112.551(2)°
Ratio:
a:b:c = 1.273 : 1 : 1.48
Unit Cell V:
366.62 ų
Z:
2
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 3.194 | (100) |
| 2.981 | (51) |
| 2.922 | (40) |
| 2.743 | (31) |
| 2.705 | (65) |
| 2.087 | (52) |
| 1.685 | (25) |
| 1.663 | (13) |
Type Occurrence of Grandaite
General Appearance of Type Material:
Thin masses or as fan-like aggregates of small (< 1 mm) crystals
Place of Conservation of Type Material:
Type material is deposited in the collections of the Museo Regionale di Scienze Naturali di Torino, Sezione di Mineralogia, Petrografia e Geologia, Torino, Italy, catalogue number M/ 15999, and Museo Civico Archeologico e di Scienze Naturali ‘‘Federico E
Geological Setting of Type Material:
Reaction between the ore minerals and hydrothermal solutions, found on the dumps of Valetta Mine.
Associated Minerals at Type Locality:
Synonyms of Grandaite
Relationship of Grandaite to other Species
Member of:
Other Members of this group:
| Arsenbrackebuschite | Pb2Fe3+(AsO4)2(OH) | Mon. 2/m : P2/m |
| Arsentsumebite | Pb2Cu(AsO4)(SO4)(OH) | Mon. 2/m : P21/m |
| Bearthite | Ca2Al(PO4)2(OH) | Mon. 2/m : P21/m |
| Brackebuschite | Pb2Mn3+(VO4)2(OH) | Mon. 2/m : P21/m |
| Bushmakinite | Pb2Al(PO4)(VO4)(OH) | Mon. 2/m : P21/m |
| Calderónite | Pb2Fe3+(VO4)2(OH) | Mon. 2/m : P21/m |
| Canosioite | Ba2Fe3+(AsO4)2(OH) | Mon. 2/m : P21/m |
| Feinglosite | Pb2Zn(AsO4)2 · H2O | Mon. 2/m |
| Ferribushmakinite | Pb2Fe3+(PO4)(VO4)(OH) | Mon. 2/m : P21/m |
| Gamagarite | Ba2Fe3+(VO4)2(OH) | Mon. 2/m : P21/m |
| Goedkenite | Sr2Al(PO4)2(OH) | Mon. 2/m : P21/m |
| Lombardoite | Ba2Mn3+(AsO4)2(OH) | Mon. 2/m : P21/m |
| Tokyoite | Ba2Mn3+(VO4)2(OH) | Mon. 2/m : P21/m |
| Tsumebite | Pb2Cu(PO4)(SO4)(OH) | Mon. 2/m : P21/m |
| Unnamed (possible ordered As-analogue of Tokyoite) | Ba2Mn[(As,V)O4]2(OH) | Mon. 2/m : P21/m |
Common Associates
Associated Minerals Based on Photo Data:
Related Minerals - Nickel-Strunz Grouping
| 8.00. | UM1997-10-AsO:CaV | (Ca, V, AsO4) ? | |
| 8.00. | Mg-Fillowite | Na2Ca(Mn2+4Mg2Fe2+)7(PO4)6 | |
| 8.00. | Strontiohurlbutite | SrBe2(PO4)2 | Mon. 2/m : P21/b |
| 8.00. | Canutite | NaMn3[AsO4][AsO3(OH)]2 | Mon. 2/m : B2/b |
| 8.00. | Metauramphite | (NH4)2(UO2)2(PO4)2·6H2O |
Other Information
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
References for Grandaite
Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Cámara, F., Ciriotti, M.E., Bittarello, E., Nestola, F., Bellatreccia, F., Massimi, F., Radica, F., Costa, E., Benna, P. and Piccoli, G.C. (2013) Grandaite, IMA 2013- 059. CNMNC Newsletter No. 18, December 2013, page 3250; Mineralogical Magazine: 77: 3249-3258.
Cámara, F., Ciriotti, M.E., Bittarello, E., Nestola, F., Massimi, F., Radica, F., Costa, E., Benna, P., Piccoli, G.C. (2014): As-bearing new mineral species from Valletta mine, Maira Valley, Piedmont, Italy: I. Grandaite, Sr2Al(AsO4)2(OH), description and crystal structure. Mineralogical Magazine: 78: 757-774.
Internet Links for Grandaite
mindat.org URL:
https://www.mindat.org/min-45951.html
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Localities for Grandaite
ⓘ - Click for 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 (eg from pseudomorphs.)
All localities listed without proper references should be considered as questionable.
- 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.
Italy (TL) | |
| Cámara, F., Ciriotti, M.E., Bittarello, E., Nestola, F., Massimi, F., Radica, F., Costa, E., Benna, P., Piccoli, G.C. (2014) As-bearing new mineral species from Valletta mine, Maira Valley, Piedmont, Italy: I. Grandaite, Sr2Al(AsO4)2(OH), description and crystal structure. Mineralogical Magazine, 78, 757-774; Cámara, F., Ciriotti, M. (2016) Polytypism, topological and crystalchemical relations among natrochalcite group and brackebuschite group minerals. EMC2016 - 2nd European Mineralogical Conference, 11-15 September 2016, Rimini, Italy, Abstracts Volume, S16-8; Cámara, F., Bittarello, E., Ciriotti, M.E., Nestola, F., Radica, F., Massimi, F., Balestra, C., Bracco, R. (2017a) As-bearing new mineral species from Valletta mine, Maira Valley, Piedmont, Italy: III. Canosioite, Ba2Fe3+(AsO4)2(OH), description and crystal structure. Mineralogical Magazine, 81, 305–317; Cámara, F., Biagioni, C., Ciriotti, M.E., Bosi, F., Kolitsch, U., Paar, W.H., Blass, G., Bittarello, E. (2017c) Piccoliite, a new mineral of the pilawite group. Congresso SIMP-SGI-SOGEI-AIV 2017, Pisa, 3-6 settembre 2017, Abstract book, page 120; http://www.socgeol.it/files/download/abstract%20book/abstract_book_pisa_2017_doi.pdf |
Valletta Mine, Vallone della Valletta, Canosio, Maira Valley, Cuneo Province, Piedmont, Italy