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Andradite from
Otjosondu, Omatako Constituency, Otjozondjupa Region, Namibia


Locality type:Deposit
Classification
Species:Andradite
Formula:Ca3Fe23+(SiO4)3
Chemical Analyses:
Oxide wt%:
12
SiO234.60 %34.60 %
TiO20.49 %0.02 %
Al2O31.16 %2.33 %
Fe2O327.90 %25.30 %
MnO12.40 %21.00 %
MgO0.02 %0.14 %
CaO22.90 %15.50 %
Total:99.47 %98.89 %
Empirical formulas:
1(Ca1.90Mn1.09Mg0.01)3.00(Fe1.75Al0.13Mn0.08Ti0.03)1.99Si2.97O12
2(Ca1.51Mn1.47Mg0.02)3.00(Fe1.68Al0.24Mn0.06Ti0.01)1.99Si3.06O12
Sample references:
1OT-23
Amthauer, Georg; Katz-Lehnert, Kerstin; Lattard, Dominique; Okrusch, Martin; Woermann, Eduard (1989) Crystal chemistry of natural Mn3+-bearing calderite-andradite garnets from Otjosondu, SWA/Namibia. Zeitschrift für Kristallographie, 189 (1-2). 43-56 doi:10.1524/zkri.1989.189.1-2.43
2OT16
Amthauer, Georg; Katz-Lehnert, Kerstin; Lattard, Dominique; Okrusch, Martin; Woermann, Eduard (1989) Crystal chemistry of natural Mn3+-bearing calderite-andradite garnets from Otjosondu, SWA/Namibia. Zeitschrift für Kristallographie, 189 (1-2). 43-56 doi:10.1524/zkri.1989.189.1-2.43
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Andradite data
Locality Data:Click here to view Otjosondu, Omatako Constituency, Otjozondjupa Region, Namibia
Data Identifiers
Mindat Occurrence Record ID:655316
Long-form Identifier:1:3:655316:6
GUID (UUID V4):0
References
Amthauer, Georg; Katz-Lehnert, Kerstin; Lattard, Dominique; Okrusch, Martin; Woermann, Eduard (1989) Crystal chemistry of natural Mn3+-bearing calderite-andradite garnets from Otjosondu, SWA/Namibia. Zeitschrift für Kristallographie, 189 (1-2). 43-56 doi:10.1524/zkri.1989.189.1-2.43
von Bezing, Ludi (2007) Namibia - Minerals and Localities (1st ed.). Bode Verlag GmbH.
CABRAL, A. R.; MOORE, J. M.; MAPANI, B. S.; KOUBOVA, M.; SATTLER, C.- D. (2011) Geochemical and mineralogical constraints on the genesis of the Otjosondu ferromanganese deposit, Namibia: hydrothermal exhalative versus hydrogenetic (including snowball-earth) origins. South African Journal of Geology, 114 (1). 57-76 doi:10.2113/gssajg.114.1.57
 
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