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Maromby pegmatite (Andreba), Ambatosoratra Commune, Ambatondrazaka District, Alaotra-Mangoro, Madagascari
Regional Level Types
Maromby pegmatite (Andreba)Pegmatite
Ambatosoratra CommuneCommune
Ambatondrazaka DistrictDistrict
Alaotra-MangoroRegion
MadagascarCountry

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06781220017272287708112.jpg
Amethyst

Maromby pegmatite, Ambatosoratra Commune, Ambatondrazaka District, Alaotra-Mangoro, Madagascar
06781220017272287708112.jpg
Amethyst

Maromby pegmatite, Ambatosoratra Commune, Ambatondrazaka District, Alaotra-Mangoro, Madagascar
08000830017272271953705.jpg
Amethyst

Maromby pegmatite, Ambatosoratra Commune, Ambatondrazaka District, Alaotra-Mangoro, Madagascar
Latitude & Longitude (WGS84):
17° 39' 11'' South , 48° 31' 4'' East
Latitude & Longitude (decimal):
-17.65333,48.51778
GRN:
S12E33
Type:
Pegmatite
Köppen climate type:
Cfa : Humid subtropical climate
Nearest Settlements:
PlacePopulationDistance
Ambatondrazaka43,134 (2018)22.7km
Amparafaravola51,519 (2018)32.0km
Sahatavy10,000 (2018)55.9km
Mindat Locality ID:
193345
Long-form identifier:
mindat:1:2:193345:4
GUID (UUID V4):
0
Other Languages:
Malagasy:
Maromby, Kaominin' Ambatosoratra, Distrikan' Ambatondrazaka, Faritr' Alaotra-Mangoro, Madagasikara


An unnamed LCT pegmatite of the chrysoberyl subtype located south-southeast of the village of Andreba, and 700m southwest of Maromby on the eastern shore of Lake Alaotra. Good specimens of chrysoberyl twins were found here in 1997.
The locality was described by Lacroix (1922) as Andreba. The locality is found on the left side of the small Maromby stream (also called Antanifotsy stream).

Possible coordinates, based on Google Earth, may be 17°39'12.01"S 48°31'4.01"E [A guess, must be verified].

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


7 valid minerals.

Rock Types Recorded


Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Beryl
Formula: Be3Al2(Si6O18)
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Chrysoberyl
Formula: BeAl2O4
ⓘ 'Columbite-(Fe)-Columbite-(Mn) Series'
ⓘ Dumortierite
Formula: Al(Al2O)(Al2O)2(SiO4)3(BO3)
ⓘ Microcline
Formula: K(AlSi3O8)
ⓘ 'Monazite Group'
Formula: REE(PO4)
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Quartz
Formula: SiO2
Description: pseudo-cubic septer amethyst
ⓘ Quartz var. Amethyst
Formula: SiO2
Description: pseudo-cubic septer amethyst
ⓘ Quartz var. Smoky Quartz
Formula: SiO2
ⓘ 'Tourmaline'
Formula: AD3G6(T6O18)(BO3)3X3Z
ⓘ Vermiculite
Formula: Mg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘChrysoberyl4.BA.05BeAl2O4
ⓘQuartz
var. Amethyst		4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
Group 9 - Silicates
ⓘDumortierite9.AJ.10Al(Al2O)(Al2O)2(SiO4)3(BO3)
ⓘBeryl9.CJ.05Be3Al2(Si6O18)
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘVermiculite9.EC.50Mg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
ⓘMicrocline9.FA.30K(AlSi3O8)
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Monazite Group'-REE(PO4)
ⓘ'Tourmaline'-AD3G6(T6O18)(BO3)3X3Z
ⓘ'Columbite-(Fe)-Columbite-(Mn) Series'-

List of minerals for each chemical element

HHydrogen
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
BeBeryllium
Beⓘ BerylBe3Al2(Si6O18)
Beⓘ ChrysoberylBeAl2O4
BBoron
Bⓘ DumortieriteAl(Al2O)(Al2O)2(SiO4)3(BO3)
Bⓘ TourmalineAD3G6(T6O18)(BO3)3X3Z
OOxygen
Oⓘ Quartz var. AmethystSiO2
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ BerylBe3Al2(Si6O18)
Oⓘ ChrysoberylBeAl2O4
Oⓘ DumortieriteAl(Al2O)(Al2O)2(SiO4)3(BO3)
Oⓘ MicroclineK(AlSi3O8)
Oⓘ Monazite GroupREE(PO4)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ Quartz var. Smoky QuartzSiO2
Oⓘ TourmalineAD3G6(T6O18)(BO3)3X3Z
Oⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Oⓘ Columbite-(Fe)-Columbite-(Mn) Series
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
AlAluminium
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ BerylBe3Al2(Si6O18)
Alⓘ ChrysoberylBeAl2O4
Alⓘ DumortieriteAl(Al2O)(Al2O)2(SiO4)3(BO3)
Alⓘ MicroclineK(AlSi3O8)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
SiSilicon
Siⓘ Quartz var. AmethystSiO2
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ BerylBe3Al2(Si6O18)
Siⓘ DumortieriteAl(Al2O)(Al2O)2(SiO4)3(BO3)
Siⓘ MicroclineK(AlSi3O8)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ Quartz var. Smoky QuartzSiO2
Siⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
PPhosphorus
Pⓘ Monazite GroupREE(PO4)
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MicroclineK(AlSi3O8)
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
MnManganese
Mnⓘ Columbite-(Fe)-Columbite-(Mn) Series
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Feⓘ Columbite-(Fe)-Columbite-(Mn) Series
NbNiobium
Nbⓘ Columbite-(Fe)-Columbite-(Mn) Series

Other Regions, Features and Areas containing this locality

AfricaContinent
African Plate
Madagascar
Somali PlateTectonic Plate

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References

Guigues, J. (1955) Étude des gisements de pegmatite de Madagascar (Deuxième partie) Travaux du Bureau Gèologique de Madagascar 67. Haut Commisariat de Madagascar et dependancespp.11-12
Pezzotta, Federico (1999) Madagaskar. Das Paradies der Mineralien und Edelsteine. extraLapis 17. Christian Weise Verlagp.48
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