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Betroka District, Anosy, Madagascari
Regional Level Types
Betroka DistrictDistrict
AnosyRegion
MadagascarCountry

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00878470017272021964290.jpg
View of the Ambatomena mica mining area, ca. 1920.

Ambatomena Toby, Bekorobo, Betroka District, Anosy, Madagascar
06906610017272024541691.jpg
View of the Betroka phlogopite mining area, ca. 1925.

Benato phlogopite mines, Benato Toby, Betroka District, Anosy, Madagascar
Largest Settlements:
PlacePopulation
Ambalasoa4,000 (2018)
Mindat Locality ID:
7007
Long-form identifier:
mindat:1:2:7007:5
GUID (UUID V4):
0
Other Languages:
French:
Betroka, Anosy, Madagascar
Italian:
Betroka, regione di Anosy, Madagascar
Malagasy:
Distrikan'i Betroka, Faritr' Anosy, Madagasikara
Simplified Chinese:
貝特魯卡, 阿諾西區, 马达加斯加
Dutch:
Betroka, Anosy, Madagaskar
Japanese:
ベトルカ, アヌシ地域圏, マダガスカル
Polish:
Betroka, Anosy, Madagaskar
Portuguese:
Betroka, Anosy, Madagáscar
Swedish:
Betroka, Anosyregionen, Madagaskar


Betroka is a district of Anosy in Madagascar.

Note on the mineral list: In the mineral markets of Antsirabe, occasionally gemmy, green single crystals of diopside coming from Betroka are erroneously sold as kornerupine, which also occurs in the district.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded from this region.


Mineral List

Mineral list contains entries from the region specified including sub-localities

53 valid minerals. 1 (TL) - type locality of valid minerals.

Rock Types Recorded


Rock list contains entries from the region specified including sub-localities

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ 'Allanite Group'
Formula: (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
Description: Found as large radioactive tabular crystals in an undislosed locality south of Isoanala (Behier 1958).
ⓘ 'Amphibole Supergroup'
Formula: AB2C5(T8O22)W2
ⓘ Analcime
Formula: Na(AlSi2O6) · H2O
ⓘ Anhydrite
Formula: CaSO4
ⓘ Anorthite
Formula: Ca(Al2Si2O8)
ⓘ Anorthite var. Labradorite
Formula: (Ca,Na)[Al(Al,Si)Si2O8]
ⓘ 'Apatite'
Formula: Ca5(PO4)3A
Localities: Reported from at least 20 localities in this region.
ⓘ Augite
Formula: (CaxMgyFez)(Mgy1Fez1)Si2O6
Description: Sample sold as kornerupine
References:
ⓘ 'Bastnäsite'
Formula: (Ce/Nd/Y/REE)(CO3)F
ⓘ Beryl
Formula: Be3Al2(Si6O18)
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Calcite
Formula: CaCO3
Localities: Reported from at least 11 localities in this region.
ⓘ Celestine
Formula: SrSO4
ⓘ 'Chabazite'
Habit: crystals < 8mm
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ Cheralite
Formula: CaTh(PO4)2
ⓘ 'Chevkinite Group'
Description: A piece weiging several kg, was found NE of the old prison, Isoanala ( Lacroix 1922)
ⓘ 'Chlorite Group'
ⓘ Cordierite
Formula: Mg2Al4Si5O18
Localities: Reported from at least 6 localities in this region.
ⓘ Corundum
Formula: Al2O3
Localities: Reported from at least 8 localities in this region.
ⓘ Corundum var. Ruby
Formula: Al2O3
ⓘ Corundum var. Sapphire
Formula: Al2O3
ⓘ Diopside
Formula: CaMgSi2O6
Localities: Reported from at least 11 localities in this region.
ⓘ Dravite
Formula: NaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
References:
Marko Burkhardt CollectionIdentification: SEM-EDS, Raman Spectroscopy
ⓘ Edenite
Formula: NaCa2Mg5(Si7Al)O22(OH)2
ⓘ Enstatite
Formula: Mg2Si2O6
Description: an enstatite with XMg values from 0.94 to 0.98, Al2O3 varies between 1.80 to 5.57 wt% and MnO is up to 0.14 wt% (Razakamanana et al. (2006)
ⓘ Enstatite var. Bronzite
Formula: (Mg,Fe2+)2[SiO3]2
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ 'Feldspar Group'
ⓘ 'Feldspar Group var. Perthite'
Colour: Pink to reddish
Description: Perthitic K-Feldspar. Sometimes Graphic Granite intergrowths with white/smoky Quartz
ⓘ Ferrohögbomite-2N2S
Formula: [(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
ⓘ Fluorite
Formula: CaF2
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ Grandidierite
Formula: (Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
ⓘ Grossular
Formula: Ca3Al2(SiO4)3
ⓘ Gypsum
Formula: CaSO4 · 2H2O
ⓘ Hercynite
Formula: Fe2+Al2O4
ⓘ 'Heulandite Subgroup'
Formula: (Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
ⓘ Ilmenite
Formula: Fe2+TiO3
ⓘ Kaolinite
Formula: Al2(Si2O5)(OH)4
ⓘ 'K Feldspar'
ⓘ Kornerupine
Formula: Mg3Al6(Si,Al,B)5O21(OH)
Description: Lacroix mentions a find of kornerupine about 20 km E of Itrongay. Behier (1960) argues for this being the Voronkafotra locality
ⓘ Laumontite
Formula: CaAl2Si4O12 · 4H2O
ⓘ Laurentthomasite (TL)
Formula: K◻2Mg2(Be2Al)[Si12O30]
Type Locality:
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Marialite
Formula: Na4Al3Si9O24Cl
References:
ⓘ 'Mica Group'
ⓘ Molybdenite
Formula: MoS2
ⓘ Opal
Formula: SiO2 · nH2O
ⓘ Opal var. Opal-CT
Formula: SiO2 · nH2O
ⓘ Orthoclase
Formula: K(AlSi3O8)
ⓘ 'Orthopyroxene Subgroup'
ⓘ Pargasite ?
Formula: NaCa2(Mg4Al)(Si6Al2)O22(OH)2
ⓘ Phenakite
Formula: Be2SiO4
ⓘ Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
Localities: Reported from at least 53 localities in this region.
ⓘ 'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
ⓘ Prehnite
Formula: Ca2Al2Si3O10(OH)2
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrophyllite
Formula: Al2Si4O10(OH)2
ⓘ 'Pyroxene Group'
Formula: ADSi2O6
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2
Localities: Reported from at least 6 localities in this region.
ⓘ Quartz var. Chalcedony
Formula: SiO2
ⓘ Quartz var. Smoky Quartz
Formula: SiO2
ⓘ Rutile
Formula: TiO2
ⓘ Sanidine
Formula: K(AlSi3O8)
Habit: Prismatic
Colour: Yellow
Description: All the gemmy yellow "Orthoclase" is Sanidine
ⓘ Sapphirine
Formula: Mg4(Mg3Al9)O4[Si3Al9O36]
Localities: Reported from at least 10 localities in this region.
Description: A sapphirine-bearing anatectic Al-Mg granulite is described in Razakamanana et al (2006)
ⓘ 'Scapolite'
Localities: Reported from at least 8 localities in this region.
Colour: Pale yellow
ⓘ 'Scapolite var. Wernerite'
ⓘ Sillimanite
Formula: Al2(SiO4)O
ⓘ Spessartine
Formula: Mn2+3Al2(SiO4)3
ⓘ Spinel
Formula: MgAl2O4
Localities: Reported from at least 21 localities in this region.
ⓘ Spinel var. Pleonaste
Formula: (Mg,Fe)Al2O4
ⓘ 'Stilbite Subgroup'
Formula: M6-7[Al8-9Si27-28O72] · nH2O
ⓘ Talc
Formula: Mg3Si4O10(OH)2
ⓘ Talc var. Steatite
Formula: Mg3(Si4O10)(OH)2
ⓘ Thorianite
Formula: ThO2
ⓘ Thorite
Formula: Th(SiO4)
ⓘ Thorite var. Orangite
Formula: Th(SiO4)
ⓘ Thortveitite
Formula: Sc2Si2O7
ⓘ Titanite
Formula: CaTiO(SiO4)
Localities: Reported from at least 6 localities in this region.
ⓘ 'Tourmaline'
Formula: AD3G6(T6O18)(BO3)3X3Z
Colour: green
ⓘ 'Tourmaline var. Indicolite'
ⓘ Zircon
Formula: Zr(SiO4)
Localities: Reported from at least 8 localities in this region.
Description: Microscopically grains in a sapphirine-bearing anatectic Al-Mg granulite

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘMolybdenite2.EA.30MoS2
ⓘPyrite2.EB.05aFeS2
Group 3 - Halides
ⓘFluorite3.AB.25CaF2
Group 4 - Oxides and Hydroxides
ⓘHercynite4.BB.05Fe2+Al2O4
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘSpinel4.BB.05MgAl2O4
ⓘvar. Pleonaste4.BB.05(Mg,Fe)Al2O4
ⓘFerrohögbomite-2N2S4.CB.[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
ⓘCorundum4.CB.05Al2O3
ⓘIlmenite4.CB.05Fe2+TiO3
ⓘCorundum
var. Ruby
4.CB.05Al2O3
ⓘvar. Sapphire4.CB.05Al2O3
ⓘQuartz
var. Chalcedony
4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
ⓘOpal4.DA.10SiO2 · nH2O
ⓘvar. Opal-CT4.DA.10SiO2 · nH2O
ⓘRutile4.DB.05TiO2
ⓘThorianite4.DL.05ThO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘAnhydrite7.AD.30CaSO4
ⓘCelestine7.AD.35SrSO4
ⓘGypsum7.CD.40CaSO4 · 2H2O
Group 8 - Phosphates, Arsenates and Vanadates
ⓘCheralite8.AD.50CaTh(PO4)2
Group 9 - Silicates
ⓘPhenakite9.AA.05Be2SiO4
ⓘGrossular9.AD.25Ca3Al2(SiO4)3
ⓘSpessartine9.AD.25Mn2+3Al2(SiO4)3
ⓘThorite
var. Orangite
9.AD.30Th(SiO4)
ⓘ9.AD.30Th(SiO4)
ⓘZircon9.AD.30Zr(SiO4)
ⓘSillimanite9.AF.05Al2(SiO4)O
ⓘTitanite9.AG.15CaTiO(SiO4)
ⓘGrandidierite9.AJ.05(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
ⓘThortveitite9.BC.05Sc2Si2O7
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘKornerupine9.BJ.50Mg3Al6(Si,Al,B)5O21(OH)
ⓘBeryl9.CJ.05Be3Al2(Si6O18)
ⓘCordierite9.CJ.10Mg2Al4Si5O18
ⓘDravite9.CK.05NaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
ⓘLaurentthomasite (TL)9.CM.05K◻2Mg2(Be2Al)[Si12O30]
ⓘEnstatite9.DA.05Mg2Si2O6
ⓘvar. Bronzite9.DA.05(Mg,Fe2+)2[SiO3]2
ⓘAugite9.DA.15(CaxMgyFez)(Mgy1Fez1)Si2O6
ⓘDiopside9.DA.15CaMgSi2O6
ⓘEdenite9.DE.15NaCa2Mg5(Si7Al)O22(OH)2
ⓘPargasite ?9.DE.15NaCa2(Mg4Al)(Si6Al2)O22(OH)2
ⓘSapphirine9.DH.45Mg4(Mg3Al9)O4[Si3Al9O36]
ⓘPrehnite9.DP.20Ca2Al2Si3O10(OH)2
ⓘTalc
var. Steatite
9.EC.05Mg3(Si4O10)(OH)2
ⓘ9.EC.05Mg3Si4O10(OH)2
ⓘPyrophyllite9.EC.10Al2Si4O10(OH)2
ⓘPhlogopite9.EC.20KMg3(AlSi3O10)(OH)2
ⓘKaolinite9.ED.05Al2(Si2O5)(OH)4
ⓘOrthoclase9.FA.30K(AlSi3O8)
ⓘSanidine9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
ⓘAnorthite9.FA.35Ca(Al2Si2O8)
ⓘvar. Labradorite9.FA.35(Ca,Na)[Al(Al,Si)Si2O8]
ⓘMarialite9.FB.15Na4Al3Si9O24Cl
ⓘAnalcime9.GB.05Na(AlSi2O6) · H2O
ⓘLaumontite9.GB.10CaAl2Si4O12 · 4H2O
Unclassified
ⓘ'Amphibole Supergroup'-AB2C5(T8O22)W2
ⓘ'Bastnäsite'-(Ce/Nd/Y/REE)(CO3)F
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Chabazite'-
ⓘ'Chlorite Group'-
ⓘ'Feldspar Group'-
ⓘ'Heulandite Subgroup'-(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
ⓘ'Tourmaline
var. Indicolite'
-AD3G6(T6O18)(BO3)3X3Z
ⓘ'Stilbite Subgroup'-M6-7[Al8-9Si27-28O72] · nH2O
ⓘ'Tourmaline'-AD3G6(T6O18)(BO3)3X3Z
ⓘ'Scapolite
var. Wernerite'
-
ⓘ'Feldspar Group
var. Perthite'
-
ⓘ'Mica Group'-
ⓘ'Scapolite'-
ⓘ'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8
ⓘ'K Feldspar'-
ⓘ'Pyroxene Group'-ADSi2O6
ⓘ'Garnet Group'-X3Z2(SiO4)3
ⓘ'Orthopyroxene Subgroup'-
ⓘ'Apatite'-Ca5(PO4)3A
ⓘ'Chevkinite Group'-
ⓘ'Allanite Group'-(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)

List of minerals for each chemical element

HHydrogen
Hⓘ AnalcimeNa(AlSi2O6) · H2O
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Hⓘ EdeniteNaCa2Mg5(Si7Al)O22(OH)2
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ GypsumCaSO4 · 2H2O
Hⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Hⓘ KaoliniteAl2(Si2O5)(OH)4
Hⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Hⓘ LaumontiteCaAl2Si4O12 · 4H2O
Hⓘ OpalSiO2 · nH2O
Hⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Hⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Hⓘ PrehniteCa2Al2Si3O10(OH)2
Hⓘ PyrophylliteAl2Si4O10(OH)2
Hⓘ Talc var. SteatiteMg3(Si4O10)(OH)2
Hⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Hⓘ TalcMg3Si4O10(OH)2
Hⓘ Ferrohögbomite-2N2S[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
Hⓘ Opal var. Opal-CTSiO2 · nH2O
Hⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
BeBeryllium
Beⓘ BerylBe3Al2(Si6O18)
Beⓘ PhenakiteBe2SiO4
Beⓘ LaurentthomasiteK◻2Mg2(Be2Al)[Si12O30]
BBoron
Bⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Bⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Bⓘ Tourmaline var. Indicolite
Bⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Bⓘ TourmalineAD3G6(T6O18)(BO3)3X3Z
CCarbon
Cⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
Cⓘ CalciteCaCO3
Cⓘ Scapolite var. Wernerite
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Amphibole SupergroupAB2C5(T8O22)W2
Oⓘ AnalcimeNa(AlSi2O6) · H2O
Oⓘ AnhydriteCaSO4
Oⓘ AnorthiteCa(Al2Si2O8)
Oⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Oⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ BerylBe3Al2(Si6O18)
Oⓘ CalciteCaCO3
Oⓘ CelestineSrSO4
Oⓘ Quartz var. ChalcedonySiO2
Oⓘ CordieriteMg2Al4Si5O18
Oⓘ CorundumAl2O3
Oⓘ DiopsideCaMgSi2O6
Oⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Oⓘ EdeniteNaCa2Mg5(Si7Al)O22(OH)2
Oⓘ EnstatiteMg2Si2O6
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Oⓘ GrossularCa3Al2(SiO4)3
Oⓘ GypsumCaSO4 · 2H2O
Oⓘ HercyniteFe2+Al2O4
Oⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Oⓘ IlmeniteFe2+TiO3
Oⓘ Tourmaline var. Indicolite
Oⓘ KaoliniteAl2(Si2O5)(OH)4
Oⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Oⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
Oⓘ LaumontiteCaAl2Si4O12 · 4H2O
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MarialiteNa4Al3Si9O24Cl
Oⓘ OpalSiO2 · nH2O
Oⓘ Thorite var. OrangiteTh(SiO4)
Oⓘ OrthoclaseK(AlSi3O8)
Oⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Oⓘ PhenakiteBe2SiO4
Oⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Oⓘ PrehniteCa2Al2Si3O10(OH)2
Oⓘ PyrophylliteAl2Si4O10(OH)2
Oⓘ QuartzSiO2
Oⓘ Corundum var. RubyAl2O3
Oⓘ RutileTiO2
Oⓘ SanidineK(AlSi3O8)
Oⓘ Corundum var. SapphireAl2O3
Oⓘ SapphirineMg4(Mg3Al9)O4[Si3Al9O36]
Oⓘ SillimaniteAl2(SiO4)O
Oⓘ Quartz var. Smoky QuartzSiO2
Oⓘ SpessartineMn32+Al2(SiO4)3
Oⓘ SpinelMgAl2O4
Oⓘ Talc var. SteatiteMg3(Si4O10)(OH)2
Oⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ ThorianiteThO2
Oⓘ ThoriteTh(SiO4)
Oⓘ ThortveititeSc2Si2O7
Oⓘ TitaniteCaTiO(SiO4)
Oⓘ TourmalineAD3G6(T6O18)(BO3)3X3Z
Oⓘ Scapolite var. Wernerite
Oⓘ ZirconZr(SiO4)
Oⓘ Enstatite var. Bronzite(Mg,Fe2+)2[SiO3]2
Oⓘ Spinel var. Pleonaste(Mg,Fe)Al2O4
Oⓘ CheraliteCaTh(PO4)2
Oⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Oⓘ Pyroxene GroupADSi2O6
Oⓘ Garnet GroupX3Z2(SiO4)3
Oⓘ Ferrohögbomite-2N2S[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
Oⓘ ApatiteCa5(PO4)3A
Oⓘ Opal var. Opal-CTSiO2 · nH2O
Oⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
Oⓘ LaurentthomasiteK◻2Mg2(Be2Al)[Si12O30]
FFluorine
Fⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fⓘ FluoriteCaF2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
Naⓘ AnalcimeNa(AlSi2O6) · H2O
Naⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Naⓘ EdeniteNaCa2Mg5(Si7Al)O22(OH)2
Naⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Naⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
Naⓘ MarialiteNa4Al3Si9O24Cl
Naⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Naⓘ Scapolite var. Wernerite
Naⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mgⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ CordieriteMg2Al4Si5O18
Mgⓘ DiopsideCaMgSi2O6
Mgⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Mgⓘ EdeniteNaCa2Mg5(Si7Al)O22(OH)2
Mgⓘ EnstatiteMg2Si2O6
Mgⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Mgⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Mgⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Mgⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Mgⓘ SapphirineMg4(Mg3Al9)O4[Si3Al9O36]
Mgⓘ SpinelMgAl2O4
Mgⓘ Talc var. SteatiteMg3(Si4O10)(OH)2
Mgⓘ TalcMg3Si4O10(OH)2
Mgⓘ Enstatite var. Bronzite(Mg,Fe2+)2[SiO3]2
Mgⓘ Spinel var. Pleonaste(Mg,Fe)Al2O4
Mgⓘ Ferrohögbomite-2N2S[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
Mgⓘ LaurentthomasiteK◻2Mg2(Be2Al)[Si12O30]
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ AnalcimeNa(AlSi2O6) · H2O
Alⓘ AnorthiteCa(Al2Si2O8)
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ BerylBe3Al2(Si6O18)
Alⓘ CordieriteMg2Al4Si5O18
Alⓘ CorundumAl2O3
Alⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Alⓘ EdeniteNaCa2Mg5(Si7Al)O22(OH)2
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Alⓘ GrossularCa3Al2(SiO4)3
Alⓘ HercyniteFe2+Al2O4
Alⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Alⓘ KaoliniteAl2(Si2O5)(OH)4
Alⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Alⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
Alⓘ LaumontiteCaAl2Si4O12 · 4H2O
Alⓘ MarialiteNa4Al3Si9O24Cl
Alⓘ OrthoclaseK(AlSi3O8)
Alⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Alⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Alⓘ PrehniteCa2Al2Si3O10(OH)2
Alⓘ PyrophylliteAl2Si4O10(OH)2
Alⓘ Corundum var. RubyAl2O3
Alⓘ SanidineK(AlSi3O8)
Alⓘ Corundum var. SapphireAl2O3
Alⓘ SapphirineMg4(Mg3Al9)O4[Si3Al9O36]
Alⓘ SillimaniteAl2(SiO4)O
Alⓘ SpessartineMn32+Al2(SiO4)3
Alⓘ SpinelMgAl2O4
Alⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Alⓘ Scapolite var. Wernerite
Alⓘ Spinel var. Pleonaste(Mg,Fe)Al2O4
Alⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Alⓘ Ferrohögbomite-2N2S[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
Alⓘ LaurentthomasiteK◻2Mg2(Be2Al)[Si12O30]
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ AnalcimeNa(AlSi2O6) · H2O
Siⓘ AnorthiteCa(Al2Si2O8)
Siⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ BerylBe3Al2(Si6O18)
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ CordieriteMg2Al4Si5O18
Siⓘ DiopsideCaMgSi2O6
Siⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Siⓘ EdeniteNaCa2Mg5(Si7Al)O22(OH)2
Siⓘ EnstatiteMg2Si2O6
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Siⓘ GrossularCa3Al2(SiO4)3
Siⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Siⓘ KaoliniteAl2(Si2O5)(OH)4
Siⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Siⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
Siⓘ LaumontiteCaAl2Si4O12 · 4H2O
Siⓘ MarialiteNa4Al3Si9O24Cl
Siⓘ OpalSiO2 · nH2O
Siⓘ Thorite var. OrangiteTh(SiO4)
Siⓘ OrthoclaseK(AlSi3O8)
Siⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Siⓘ PhenakiteBe2SiO4
Siⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Siⓘ PrehniteCa2Al2Si3O10(OH)2
Siⓘ PyrophylliteAl2Si4O10(OH)2
Siⓘ QuartzSiO2
Siⓘ SanidineK(AlSi3O8)
Siⓘ SapphirineMg4(Mg3Al9)O4[Si3Al9O36]
Siⓘ SillimaniteAl2(SiO4)O
Siⓘ Quartz var. Smoky QuartzSiO2
Siⓘ SpessartineMn32+Al2(SiO4)3
Siⓘ Talc var. SteatiteMg3(Si4O10)(OH)2
Siⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ ThoriteTh(SiO4)
Siⓘ ThortveititeSc2Si2O7
Siⓘ TitaniteCaTiO(SiO4)
Siⓘ Scapolite var. Wernerite
Siⓘ ZirconZr(SiO4)
Siⓘ Enstatite var. Bronzite(Mg,Fe2+)2[SiO3]2
Siⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Siⓘ Pyroxene GroupADSi2O6
Siⓘ Garnet GroupX3Z2(SiO4)3
Siⓘ Opal var. Opal-CTSiO2 · nH2O
Siⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
Siⓘ LaurentthomasiteK◻2Mg2(Be2Al)[Si12O30]
PPhosphorus
Pⓘ CheraliteCaTh(PO4)2
Pⓘ ApatiteCa5(PO4)3A
SSulfur
Sⓘ AnhydriteCaSO4
Sⓘ CelestineSrSO4
Sⓘ ChalcopyriteCuFeS2
Sⓘ GypsumCaSO4 · 2H2O
Sⓘ MolybdeniteMoS2
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
ClChlorine
Clⓘ MarialiteNa4Al3Si9O24Cl
Clⓘ Scapolite var. Wernerite
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Kⓘ OrthoclaseK(AlSi3O8)
Kⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Kⓘ SanidineK(AlSi3O8)
Kⓘ LaurentthomasiteK◻2Mg2(Be2Al)[Si12O30]
CaCalcium
Caⓘ AnhydriteCaSO4
Caⓘ AnorthiteCa(Al2Si2O8)
Caⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Caⓘ CalciteCaCO3
Caⓘ DiopsideCaMgSi2O6
Caⓘ EdeniteNaCa2Mg5(Si7Al)O22(OH)2
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ FluoriteCaF2
Caⓘ GrossularCa3Al2(SiO4)3
Caⓘ GypsumCaSO4 · 2H2O
Caⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Caⓘ Anorthite var. Labradorite(Ca,Na)[Al(Al,Si)Si2O8]
Caⓘ LaumontiteCaAl2Si4O12 · 4H2O
Caⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Caⓘ PrehniteCa2Al2Si3O10(OH)2
Caⓘ TitaniteCaTiO(SiO4)
Caⓘ Scapolite var. Wernerite
Caⓘ CheraliteCaTh(PO4)2
Caⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Caⓘ ApatiteCa5(PO4)3A
ScScandium
Scⓘ ThortveititeSc2Si2O7
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ IlmeniteFe2+TiO3
Tiⓘ RutileTiO2
Tiⓘ TitaniteCaTiO(SiO4)
Tiⓘ Ferrohögbomite-2N2S[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
MnManganese
Mnⓘ SpessartineMn32+Al2(SiO4)3
FeIron
Feⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ ChalcopyriteCuFeS2
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Feⓘ HercyniteFe2+Al2O4
Feⓘ IlmeniteFe2+TiO3
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
Feⓘ Enstatite var. Bronzite(Mg,Fe2+)2[SiO3]2
Feⓘ Spinel var. Pleonaste(Mg,Fe)Al2O4
Feⓘ Ferrohögbomite-2N2S[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
CuCopper
Cuⓘ ChalcopyriteCuFeS2
ZnZinc
Znⓘ Ferrohögbomite-2N2S[(Fe2+,Mg,Zn,Al)3(Al,Ti,Fe3+)8O15(OH)]2
SrStrontium
Srⓘ CelestineSrSO4
YYttrium
Yⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
ZrZirconium
Zrⓘ ZirconZr(SiO4)
MoMolybdenum
Moⓘ MolybdeniteMoS2
CeCerium
Ceⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
NdNeodymium
Ndⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
ThThorium
Thⓘ Thorite var. OrangiteTh(SiO4)
Thⓘ ThorianiteThO2
Thⓘ ThoriteTh(SiO4)
Thⓘ CheraliteCaTh(PO4)2

Geochronology

Mineralization age: Cambrian : 490 ± 20 Ma to 487 ± 4 Ma

Important note: This table is based only on rock and mineral ages recorded on mindat.org for this locality and is not necessarily a complete representation of the geochronology, but does give an indication of possible mineralization events relevant to this locality. As more age information is added this table may expand in the future. A break in the table simply indicates a lack of data entered here, not necessarily a break in the geologic sequence. Grey background entries are from different, related, localities.

Geologic TimeRocks, Minerals and Events
Phanerozoic
 Paleozoic
  Cambrian
   Furongian
ⓘ Biotite487 ± 4 MaAmbatomena ruby deposit, Isoanala, Betroka District, Anosy, Madagascar
ⓘ Thorianite490 ± 20 Ma
ⓘ Zircon490 ± 20 MaItrongay (Itrongahy), Mahasoa Est, Betroka District, Anosy, Madagascar

Fossils

This region is too big or complex to display the fossil list, try looking at smaller subregions.

Other Databases

Wikipedia:https://en.wikipedia.org/wiki/Betroka_(district)
Wikidata ID:Q2900147
GeoNames ID:8299289

Localities in this Region

Other Regions, Features and Areas that Intersect

AfricaContinent
African Plate
Somali PlateTectonic Plate

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

 
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