Emerald open pit mine in the rainforest region of eastern Madagascar, located near the village of Kianjovato, approx. 60 km west of the town of Mananjary. The village of Kianjovato is, since the village is situated along the RN 25 road, often used as a referencepoint in several written papers on this mine, but it is in fact situated in the commune north of the Kianjovato Commune.

The emeralds occurs here in the contact zone between pegmatite and biotite schists. The emeralds were formed by metasomatic processes at the contact between pegmatites and hornblendites related to a Pan-African tectonometamorphic event.
Based on fluid-inclusion data, the conditions of emerald growth were 250°C < T < 450°C and P = 1.5 kbar (Vapnik et al. 2006).

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Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.

ⓘ Gemstones

Mineral List

10 valid minerals.

Rock Types Recorded

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Alphabetical List Tree Diagram

ⓘ 'Biotite schist'

ⓘ Hornblendite

ⓘ 'Pegmatite'

Detailed Mineral List:

ⓘ 'Apatite'

Formula: Ca₅(PO₄)₃A

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

ⓘ Beryl

Formula: Be₃Al₂(Si₆O₁₈)

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

Vapnik, Ye., Moroz, I., Roth, M., Eliezri, I. (2006) Formation of emeralds at pegmatite-ultramafic contacts based on fluid inclusions in Kianjavato emerald, Mananjary deposits, Madagascar. Mineralogical Magazine, 70 (2) 141-158 doi:10.1180/0026461067020320

ⓘ Beryl var. Emerald

Formula: Be₃Al₂(Si₆O₁₈)

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

ⓘ 'Biotite'

Formula: K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂

Colour: Brown

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

ⓘ 'Chlorite Group'

References:

ⓘ Dolomite

Formula: CaMg(CO₃)₂

References:

ⓘ Goethite

Formula: Fe³⁺O(OH)

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

ⓘ Hematite

Formula: Fe₂O₃

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

ⓘ Ilmenite

Formula: Fe²⁺TiO₃

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

ⓘ Phlogopite

Formula: KMg₃(AlSi₃O₁₀)(OH)₂

References:

ⓘ Quartz

Formula: SiO₂

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

ⓘ Roscoelite ?

Formula: KV³⁺₂(AlSi₃O₁₀)(OH)₂

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

ⓘ Rutile

Formula: TiO₂

References:

ⓘ Talc

Formula: Mg₃Si₄O₁₀(OH)₂

References:

ⓘ 'Tourmaline'

Formula: AD₃G₆(T₆O₁₈)(BO₃)₃X₃Z

References:

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘ	Goethite	4.00.	Fe³⁺O(OH)
ⓘ	Hematite	4.CB.05	Fe₂O₃
ⓘ	Ilmenite	4.CB.05	Fe²⁺TiO₃
ⓘ	Quartz	4.DA.05	SiO₂
ⓘ	Rutile	4.DB.05	TiO₂
Group 5 - Nitrates and Carbonates
ⓘ	Dolomite	5.AB.10	CaMg(CO₃)₂
Group 9 - Silicates
ⓘ	Beryl	9.CJ.05	Be₃Al₂(Si₆O₁₈)
ⓘ	var. Emerald	9.CJ.05	Be₃Al₂(Si₆O₁₈)
ⓘ	Talc	9.EC.05	Mg₃Si₄O₁₀(OH)₂
ⓘ	Roscoelite ?	9.EC.15	KV³⁺₂(AlSi₃O₁₀)(OH)₂
ⓘ	Phlogopite	9.EC.20	KMg₃(AlSi₃O₁₀)(OH)₂
Unclassified
ⓘ	'Biotite'	-	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
ⓘ	'Chlorite Group'	-
ⓘ	'Tourmaline'	-	AD₃G₆(T₆O₁₈)(BO₃)₃X₃Z
ⓘ	'Apatite'	-	Ca₅(PO₄)₃A

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
H	ⓘ Goethite	Fe³⁺O(OH)
H	ⓘ Phlogopite	KMg₃(AlSi₃O₁₀)(OH)₂
H	ⓘ Roscoelite	KV₂³⁺(AlSi₃O₁₀)(OH)₂
H	ⓘ Talc	Mg₃Si₄O₁₀(OH)₂
Be	Beryllium
Be	ⓘ Beryl	Be₃Al₂(Si₆O₁₈)
Be	ⓘ Beryl var. Emerald	Be₃Al₂(Si₆O₁₈)
B	Boron
B	ⓘ Tourmaline	AD₃G₆(T₆O₁₈)(BO₃)₃X₃Z
C	Carbon
C	ⓘ Dolomite	CaMg(CO₃)₂
O	Oxygen
O	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
O	ⓘ Beryl	Be₃Al₂(Si₆O₁₈)
O	ⓘ Dolomite	CaMg(CO₃)₂
O	ⓘ Beryl var. Emerald	Be₃Al₂(Si₆O₁₈)
O	ⓘ Goethite	Fe³⁺O(OH)
O	ⓘ Hematite	Fe₂O₃
O	ⓘ Ilmenite	Fe²⁺TiO₃
O	ⓘ Phlogopite	KMg₃(AlSi₃O₁₀)(OH)₂
O	ⓘ Quartz	SiO₂
O	ⓘ Roscoelite	KV₂³⁺(AlSi₃O₁₀)(OH)₂
O	ⓘ Rutile	TiO₂
O	ⓘ Talc	Mg₃Si₄O₁₀(OH)₂
O	ⓘ Tourmaline	AD₃G₆(T₆O₁₈)(BO₃)₃X₃Z
O	ⓘ Apatite	Ca₅(PO₄)₃A
F	Fluorine
F	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Mg	Magnesium
Mg	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Mg	ⓘ Dolomite	CaMg(CO₃)₂
Mg	ⓘ Phlogopite	KMg₃(AlSi₃O₁₀)(OH)₂
Mg	ⓘ Talc	Mg₃Si₄O₁₀(OH)₂
Al	Aluminium
Al	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Al	ⓘ Beryl	Be₃Al₂(Si₆O₁₈)
Al	ⓘ Beryl var. Emerald	Be₃Al₂(Si₆O₁₈)
Al	ⓘ Phlogopite	KMg₃(AlSi₃O₁₀)(OH)₂
Al	ⓘ Roscoelite	KV₂³⁺(AlSi₃O₁₀)(OH)₂
Si	Silicon
Si	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Si	ⓘ Beryl	Be₃Al₂(Si₆O₁₈)
Si	ⓘ Beryl var. Emerald	Be₃Al₂(Si₆O₁₈)
Si	ⓘ Phlogopite	KMg₃(AlSi₃O₁₀)(OH)₂
Si	ⓘ Quartz	SiO₂
Si	ⓘ Roscoelite	KV₂³⁺(AlSi₃O₁₀)(OH)₂
Si	ⓘ Talc	Mg₃Si₄O₁₀(OH)₂
P	Phosphorus
P	ⓘ Apatite	Ca₅(PO₄)₃A
K	Potassium
K	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
K	ⓘ Phlogopite	KMg₃(AlSi₃O₁₀)(OH)₂
K	ⓘ Roscoelite	KV₂³⁺(AlSi₃O₁₀)(OH)₂
Ca	Calcium
Ca	ⓘ Dolomite	CaMg(CO₃)₂
Ca	ⓘ Apatite	Ca₅(PO₄)₃A
Ti	Titanium
Ti	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Ti	ⓘ Ilmenite	Fe²⁺TiO₃
Ti	ⓘ Rutile	TiO₂
V	Vanadium
V	ⓘ Roscoelite	KV₂³⁺(AlSi₃O₁₀)(OH)₂
Fe	Iron
Fe	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Fe	ⓘ Goethite	Fe³⁺O(OH)
Fe	ⓘ Hematite	Fe₂O₃
Fe	ⓘ Ilmenite	Fe²⁺TiO₃

Other Regions, Features and Areas containing this locality

AfricaContinent

African Plate

Antongil BlockCraton

Madagascar

⭔Fianarantsoa ProvinceProvince

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

Hänni, H. A., Klein, H. H. (1982) Ein Smaragdvorkommen in Madagascar. Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft, 31 (1/2) 71-77

Groat, L.A.; Giuliani, G.; Marshall, D.D.; Turner, D. (2008) Emerald deposits and occurrences: A review. Ore Geology Reviews, 34 (1-2). 87-112 doi:10.1016/j.oregeorev.2007.09.003

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