Magnesiobeltrandoite-2N3S
This page is currently not sponsored. Click here to sponsor this page.
Formula:
(Mg6Al2)(Al18Fe3+2)O38(OH)2
Colour:
Black
Lustre:
Vitreous
Hardness:
6 - 6½
Specific Gravity:
3.93 (Calculated)
Crystal System:
Trigonal
Member of:
Type Locality:
Isostructural with:
This page provides mineralogical data about Magnesiobeltrandoite-2N3S.
Classification of Magnesiobeltrandoite-2N3S
Physical Properties of Magnesiobeltrandoite-2N3S
Vitreous
Colour:
Black
Comment:
Dark reddish-brown in thin section
Streak:
Dark brown
Hardness:
6 - 6½ on Mohs scale
Comment:
≈6–6½
Tenacity:
Brittle
Cleavage:
None Observed
Fracture:
Irregular/Uneven
Density:
3.93 g/cm3 (Calculated)
Optical Data of Magnesiobeltrandoite-2N3S
Type:
Uniaxial (-)
Pleochroism:
Weak
Comments:
With ε = deep reddish brown (along c axis) and ω = reddish brown (⊥ c). Absorption is E > O.
Comments:
An estimated mean refractive index of ca. 1.80.
Chemical Properties of Magnesiobeltrandoite-2N3S
Formula:
(Mg6Al2)(Al18Fe3+2)O38(OH)2
IMA Formula:
(Mg6Al2)(Al18Fe3+2)O38(OH)2
Crystallography of Magnesiobeltrandoite-2N3S
Crystal System:
Trigonal
Class (H-M):
3m - Ditrigonal Pyramidal
Space Group:
P3m1
Cell Parameters:
a = 5.7226(3) Å, c = 23.0231(9) Å
Ratio:
a:c = 1 : 4.023
Unit Cell V:
652.95 ų (Calculated from Unit Cell)
X-Ray Powder Diffraction
Powder Diffraction Data:
d-spacing | Intensity |
---|---|
2.858 | (42) |
2.735 | (51) |
2.484 | (46) |
2.427 | (100) |
1.568 | (29) |
1.514 | (30) |
1.438 | (42) |
1.429 | (72) |
Type Occurrence of Magnesiobeltrandoite-2N3S
General Appearance of Type Material:
As subhedral to euhedral black crystals (∼50–400μm) in a fine-grained chlorite matrix associated as inclusions to relict pre-Alpine hercynite spinels and dolomite in cm- to dm-long darker boudins, which are cut by corundum + clinochlore ± dolomite veins
Place of Conservation of Type Material:
Mineralogical collections of the Museo Regionale di Scienze Naturali, Sezione di Mineralogia, Petrografia e Geologia, via Giovanni Giolitti 36, I-10123 Torino, Italy (catalogue number M/U17182)
Empirical Formula of Type Material:
[Al18.36Mg3.96Fe2+2:52Fe3+2:08Ti0.56Cr0.40Zn0.06V3+0:03Mn0.02]Σ28O38(OH)2
Geological Setting of Type Material:
Magnesian chloritites of a metamorphosed layered mafic complex
Associated Minerals at Type Locality:
Reference:
Cámara, F., Cossio, R., Regis, D., Cerantola, V., Ciriotti, M.E., Compagnoni, R. (2018): Beltrandoite, a new root-name in the högbomite supergroup: the Mg end-member magnesiobeltrandoite-2N3S. European Journal of Mineralogy, 30: 545-558
Synonyms of Magnesiobeltrandoite-2N3S
Relationship of Magnesiobeltrandoite-2N3S to other Species
Member of:
Other Members of this group:
Högbomite Group | ||
Nigerite Group | ||
Taaffeite Group | ||
Zincovelesite-6N6S | Zn3(Fe3+,Mn3+,Al,Ti)8O15(OH) | Trig. 3m (3 2/m) : P3m1 |
Fluorescence of Magnesiobeltrandoite-2N3S
No fluorescence under UV radiation and no cathodoluminescence.
Other Information
IR Spectrum:
The Raman spectrum shows a weak and strongly polarized broad OH-characteristic absorption centred at 3364 cm-1.
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 Magnesiobeltrandoite-2N3S
Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Cámara, F., Cossio, R., Regis, D., Ciriotti, M.E., Compagnoni, R. (2016): Magnesiobeltrandoite-2N3S, IMA 2016-073. CNMNC Newsletter No. 34, December 2016, page 1318; Mineralogical Magazine: 80: 1315–1321
Cámara, F., Cossio, R., Regis, D., Cerantola, V., Ciriotti, M.E., Compagnoni, R. (2018): Beltrandoite, a new root-name in the högbomite supergroup: the Mg end-member magnesiobeltrandoite-2N3S. European Journal of Mineralogy, 30: 545-558
Internet Links for Magnesiobeltrandoite-2N3S
mindat.org URL:
https://www.mindat.org/min-50780.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
Mineral Dealers:
Localities for Magnesiobeltrandoite-2N3S
Locality List




All localities listed without proper references should be considered as questionable.
Italy (TL) | |
| Cámara, F., Cossio, R., Regis, D., Ciriotti, M.E. and Compagnoni, R. (2016) Magnesiobeltrandoite-2N3S, IMA 2016-073. CNMNC Newsletter No. 34, December 2016, page 1318; Mineralogical Magazine, 80, 1315– 1321 |
Quick NavTopClassification of Magnesiobeltrandoite-2N3SPhysical Properties of Magnesiobeltrandoite-2N3SOptical Data of Magnesiobeltrandoite-2N3SChemical Properties of Magnesiobeltrandoite-2N3SCrystallography of Magnesiobeltrandoite-2N3SX-Ray Powder DiffractionType Occurrence of Magnesiobeltrandoite-2N3SSynonymsRelationshipsFluorescence Other InformationReferences for Magnesiobeltrandoite-2N3SInternet Links for Magnesiobeltrandoite-2N3SLocalities for Magnesiobeltrandoite-2N3SLocality List