Log InRegister
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreOur ScienceMindat Newsletter [Free Download]Contact Us
Donate to MindatSponsor a PageCorporate SponsorshipSponsored Pages
Learning CenterWhat Is a Mineral?The Most Common Minerals on EarthInformation for EducatorsMindat ArticlesMindat Newsletter [Free Download]The ElementsThe Mineral Quiz
Search FormMinerals by PropertiesMinerals by ChemistryMineral Visual ExplorerAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDMinerals by CountryAlphabetical Mineral IndexAlphabetical Locality SearchMineral Association SearchList of CountriesLocalities Near MePhoto SearchSearch ArticlesSearch GlossaryThe Rock H. Currier Digital LibraryMore Search Options
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
MineralsPetrologyFossilsMeteoritesGeologic Time
Mining CompaniesStatisticsMineral MuseumsClubs & OrganizationsMineral Shows & EventsDevice SettingsTime Machine
Read DiscussionsIdentification Request
Photo SearchPhoto GalleriesSearch by ColourPhoto Colour ExplorerNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Mahasoa Est, Betroka District, Anosy, Madagascari
Regional Level Types
Mahasoa EstCommune
Betroka DistrictDistrict
AnosyRegion
MadagascarCountry

This page is currently not sponsored. Click here to sponsor this page.
PhotosMapsSearch
Type:
Mindat Locality ID:
207332
Long-form identifier:
mindat:1:2:207332:6
GUID (UUID V4):
0
Other Languages:
Malagasy:
Kaominin'i Mahasoa Atsinanana, Distrikan'i Betroka, Faritr' Anosy, Madagasikara


No description has been added for this locality. Can you add one?

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

21 valid minerals. 1 erroneous literature entry.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

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)
ⓘ 'Apatite'
Formula: Ca5(PO4)3(Cl/F/OH)
Description: A 3 cm long, transparent, greenish crystal is reported by Lacroix (1913)
ⓘ 'Bastnäsite'
Formula: (Ce/Nd/Y/REE)(CO3)F
ⓘ Beryl
Formula: Be3Al2(Si6O18)
Colour: Blue
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Calcite
Formula: CaCO3
ⓘ 'Chevkinite Group'
ⓘ Cordierite
Formula: (Mg,Fe)2Al3(AlSi5O18)
ⓘ Corundum
Formula: Al2O3
ⓘ Diopside
Formula: CaMgSi2O6
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ 'Feldspar Group'
Colour: Pink to reddish
Description: Perthitic K-Feldspar. Sometimes Graphic Granite intergrowths with white/smoky Quartz
ⓘ 'Feldspar Group var. Perthite'
Colour: Pink to reddish
Description: Perthitic K-Feldspar. Sometimes Graphic Granite intergrowths with white/smoky Quartz
ⓘ Grandidierite
Formula: (Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
ⓘ Hercynite
Formula: Fe2+Al2O4
ⓘ Ilmenite
Formula: Fe2+TiO3
ⓘ 'K Feldspar'
ⓘ Kornerupine
Formula: Mg3Al6(Si,Al,B)5O21(OH)
Description: Found in an alluvial deposit close to Itrongay (Lacroix 1939)
ⓘ Opal
Formula: SiO2 · nH2O
ⓘ Orthoclase
Formula: K(AlSi3O8)
Habit: prismatic
Colour: Yellow
Description: Gemmy facetable crystals In elder litterature called "orthoclase". All are Sanidine. X-ray studies of a bright yellow to colorless feldspar collected in 2001 at one of the localities around Itrongay and other samples showed it to be high to low sanidine, not orthoclase (Simmons and Falster 2002). Further investigations by Ackermann et al. (2005) on the cation distribution and ordering of Si, Al, Fe on the tetragonal (T1) site of a K-feldspar from Itrongay, showed it to be a monoclinic low sanidine (for more details see the paper at http://www.escholarship.org/uc/item/20f968sx ).
ⓘ Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
Localities: Reported from at least 6 localities in this region.
ⓘ 'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
ⓘ Quartz
Formula: SiO2
ⓘ 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]
✪ 'Scapolite'
Colour: Pale yellow
ⓘ Sillimanite
Formula: Al2(SiO4)O
ⓘ Spinel
Formula: MgAl2O4
ⓘ Titanite
Formula: CaTi(SiO4)O
ⓘ Zircon
Formula: Zr(SiO4)

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘHercynite4.BB.05Fe2+Al2O4
ⓘSpinel4.BB.05MgAl2O4
ⓘCorundum4.CB.05Al2O3
ⓘIlmenite4.CB.05Fe2+TiO3
ⓘQuartz
var. Chalcedony
4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
ⓘOpal4.DA.10SiO2 · nH2O
ⓘRutile4.DB.05TiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘZircon9.AD.30Zr(SiO4)
ⓘSillimanite9.AF.05Al2(SiO4)O
ⓘTitanite9.AG.15CaTi(SiO4)O
ⓘGrandidierite9.AJ.05(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘKornerupine9.BJ.50Mg3Al6(Si,Al,B)5O21(OH)
ⓘBeryl9.CJ.05Be3Al2(Si6O18)
ⓘCordierite9.CJ.10(Mg,Fe)2Al3(AlSi5O18)
ⓘDiopside9.DA.15CaMgSi2O6
ⓘSapphirine9.DH.45Mg4(Mg3Al9)O4[Si3Al9O36]
ⓘPhlogopite9.EC.20KMg3(AlSi3O10)(OH)2
ⓘOrthoclase ?9.FA.30K(AlSi3O8)
ⓘSanidine9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
Unclassified
ⓘ'Bastnäsite'-(Ce/Nd/Y/REE)(CO3)F
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Feldspar Group'-
ⓘ'var. Perthite'-
ⓘ'Scapolite'-
ⓘ'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8
ⓘ'K Feldspar'-
ⓘ'Apatite'-Ca5(PO4)3(Cl/F/OH)
ⓘ'Chevkinite Group'-

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ⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Hⓘ OpalSiO2 · nH2O
Hⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Hⓘ ApatiteCa5(PO4)3(Cl/F/OH)
BeBeryllium
Beⓘ BerylBe3Al2(Si6O18)
BBoron
Bⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Bⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
CCarbon
Cⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
Cⓘ CalciteCaCO3
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
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ⓘ Quartz var. ChalcedonySiO2
Oⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Oⓘ CorundumAl2O3
Oⓘ DiopsideCaMgSi2O6
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Oⓘ HercyniteFe2+Al2O4
Oⓘ IlmeniteFe2+TiO3
Oⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Oⓘ OpalSiO2 · nH2O
Oⓘ OrthoclaseK(AlSi3O8)
Oⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ RutileTiO2
Oⓘ SanidineK(AlSi3O8)
Oⓘ SapphirineMg4(Mg3Al9)O4[Si3Al9O36]
Oⓘ SillimaniteAl2(SiO4)O
Oⓘ Quartz var. Smoky QuartzSiO2
Oⓘ SpinelMgAl2O4
Oⓘ TitaniteCaTi(SiO4)O
Oⓘ ZirconZr(SiO4)
Oⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Oⓘ ApatiteCa5(PO4)3(Cl/F/OH)
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ⓘ ApatiteCa5(PO4)3(Cl/F/OH)
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
Naⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Mgⓘ DiopsideCaMgSi2O6
Mgⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Mgⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Mgⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Mgⓘ SapphirineMg4(Mg3Al9)O4[Si3Al9O36]
Mgⓘ SpinelMgAl2O4
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ BerylBe3Al2(Si6O18)
Alⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Alⓘ CorundumAl2O3
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Alⓘ HercyniteFe2+Al2O4
Alⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Alⓘ OrthoclaseK(AlSi3O8)
Alⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Alⓘ SanidineK(AlSi3O8)
Alⓘ SapphirineMg4(Mg3Al9)O4[Si3Al9O36]
Alⓘ SillimaniteAl2(SiO4)O
Alⓘ SpinelMgAl2O4
Alⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ BerylBe3Al2(Si6O18)
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Siⓘ DiopsideCaMgSi2O6
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Siⓘ KornerupineMg3Al6(Si,Al,B)5O21(OH)
Siⓘ OpalSiO2 · nH2O
Siⓘ OrthoclaseK(AlSi3O8)
Siⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ SanidineK(AlSi3O8)
Siⓘ SapphirineMg4(Mg3Al9)O4[Si3Al9O36]
Siⓘ SillimaniteAl2(SiO4)O
Siⓘ Quartz var. Smoky QuartzSiO2
Siⓘ TitaniteCaTi(SiO4)O
Siⓘ ZirconZr(SiO4)
Siⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
PPhosphorus
Pⓘ ApatiteCa5(PO4)3(Cl/F/OH)
ClChlorine
Clⓘ ApatiteCa5(PO4)3(Cl/F/OH)
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ OrthoclaseK(AlSi3O8)
Kⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Kⓘ SanidineK(AlSi3O8)
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ DiopsideCaMgSi2O6
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ TitaniteCaTi(SiO4)O
Caⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Caⓘ ApatiteCa5(PO4)3(Cl/F/OH)
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ IlmeniteFe2+TiO3
Tiⓘ RutileTiO2
Tiⓘ TitaniteCaTi(SiO4)O
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ Grandidierite(Mg,Fe2+)(Al,Fe3+)3(SiO4)(BO3)O2
Feⓘ HercyniteFe2+Al2O4
Feⓘ IlmeniteFe2+TiO3
YYttrium
Yⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
ZrZirconium
Zrⓘ ZirconZr(SiO4)
CeCerium
Ceⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F
NdNeodymium
Ndⓘ Bastnäsite(Ce/Nd/Y/REE)(CO3)F

Geochronology

Mineralization age: Cambrian : 490 ± 20 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
ⓘ 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

GeoNames ID:11927836

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.
 
and/or  
Mindat.org® is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Mindat® and mindat.org® are registered trademarks of the Hudson Institute of Mineralogy.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2026, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph and Ida Chau.
Content on this site may not be used to train, fine-tune, or otherwise develop artificial intelligence or machine learning models without prior written permission - see our Terms & Conditions.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: October 21, 2026 07:19:38 Page updated: August 16, 2025 09:57:45
Go to top of page