Hadjer el Hamis and Hadjer Bigli comprise several rocky pinnacles close to the southern shore of Lake Chad and immediately east of the Chari river; they are up to about 100 m high.

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Standard Detailed Gallery Strunz Chemical Elements

Mineral List

ⓘ Aegirine

6 valid minerals.

Rock Types Recorded

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

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Alphabetical List Tree Diagram

ⓘ Comenditic rhyolite

Detailed Mineral List:

ⓘ Aegirine

Formula: NaFe³⁺Si₂O₆

References:

Garde, G. 1911. Description geologique des regions situees entre le Niger et le Tchad. Thesis, University of Clermont-Ferrand. A. Hermann et Fils, Paris.

Gentil, Louis (1904) Sur l'existence de roches alcalines dans le Centre africain [On the existence of alkaline rocks in Central Africa]. Compte Rendus Hebdomadaires des Seances de l'Academie des Sciences, 139 (2) 413-414

BarBeau, J. (1956). Notice explicative sur la feuille Fort-Lamy. Carte géologique de reconnaissance à l’échelle de, 1(1000000). Gouvernement General de l'Afrique Equatoriale Francaise.

ⓘ Arfvedsonite

Formula: [Na][Na₂][Fe²⁺₄Fe³⁺]Si₈O₂₂(OH)₂

References:

Garde, G. 1911. Description geologique des regions situees entre le Niger et le Tchad. Thesis, University of Clermont-Ferrand. A. Hermann et Fils, Paris.

BarBeau, J. (1956). Notice explicative sur la feuille Fort-Lamy. Carte géologique de reconnaissance à l’échelle de, 1(1000000). Gouvernement General de l'Afrique Equatoriale Francaise.

ⓘ Magnetite

Formula: Fe²⁺Fe³⁺₂O₄

References:

Garde, G. 1911. Description geologique des regions situees entre le Niger et le Tchad. Thesis, University of Clermont-Ferrand. A. Hermann et Fils, Paris.

BarBeau, J. (1956). Notice explicative sur la feuille Fort-Lamy. Carte géologique de reconnaissance à l’échelle de, 1(1000000). Gouvernement General de l'Afrique Equatoriale Francaise.

ⓘ Quartz

Formula: SiO₂

References:

Garde, G. 1911. Description geologique des regions situees entre le Niger et le Tchad. Thesis, University of Clermont-Ferrand. A. Hermann et Fils, Paris.

BarBeau, J. (1956). Notice explicative sur la feuille Fort-Lamy. Carte géologique de reconnaissance à l’échelle de, 1(1000000). Gouvernement General de l'Afrique Equatoriale Francaise.

ⓘ Riebeckite

Formula: ◻[Na₂][Fe²⁺₃Fe³⁺₂]Si₈O₂₂(OH)₂

References:

Garde, G. 1911. Description geologique des regions situees entre le Niger et le Tchad. Thesis, University of Clermont-Ferrand. A. Hermann et Fils, Paris.

BarBeau, J. (1956). Notice explicative sur la feuille Fort-Lamy. Carte géologique de reconnaissance à l’échelle de, 1(1000000). Gouvernement General de l'Afrique Equatoriale Francaise.

ⓘ Sanidine

Formula: K(AlSi₃O₈)

References:

Garde, G. 1911. Description geologique des regions situees entre le Niger et le Tchad. Thesis, University of Clermont-Ferrand. A. Hermann et Fils, Paris.

BarBeau, J. (1956). Notice explicative sur la feuille Fort-Lamy. Carte géologique de reconnaissance à l’échelle de, 1(1000000). Gouvernement General de l'Afrique Equatoriale Francaise.

ⓘ 'Sodic amphibole'

References:

Garde, G. 1911. Description geologique des regions situees entre le Niger et le Tchad. Thesis, University of Clermont-Ferrand. A. Hermann et Fils, Paris.

BarBeau, J. (1956). Notice explicative sur la feuille Fort-Lamy. Carte géologique de reconnaissance à l’échelle de, 1(1000000). Gouvernement General de l'Afrique Equatoriale Francaise.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘ	Magnetite	4.BB.05	Fe²⁺Fe³⁺₂O₄
ⓘ	Quartz	4.DA.05	SiO₂
Group 9 - Silicates
ⓘ	Aegirine	9.DA.25	NaFe³⁺Si₂O₆
ⓘ	Arfvedsonite	9.DE.25	[Na][Na₂][Fe²⁺₄Fe³⁺]Si₈O₂₂(OH)₂
ⓘ	Riebeckite	9.DE.25	◻[Na₂][Fe²⁺₃Fe³⁺₂]Si₈O₂₂(OH)₂
ⓘ	Sanidine	9.FA.30	K(AlSi₃O₈)
Unclassified
ⓘ	'Sodic amphibole'	-

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Arfvedsonite	[Na][Na₂][Fe₄²⁺Fe³⁺]Si₈O₂₂(OH)₂
H	ⓘ Riebeckite	◻[Na₂][Fe₃²⁺Fe₂³⁺]Si₈O₂₂(OH)₂
O	Oxygen
O	ⓘ Aegirine	NaFe³⁺Si₂O₆
O	ⓘ Arfvedsonite	[Na][Na₂][Fe₄²⁺Fe³⁺]Si₈O₂₂(OH)₂
O	ⓘ Magnetite	Fe²⁺Fe₂³⁺O₄
O	ⓘ Quartz	SiO₂
O	ⓘ Riebeckite	◻[Na₂][Fe₃²⁺Fe₂³⁺]Si₈O₂₂(OH)₂
O	ⓘ Sanidine	K(AlSi₃O₈)
Na	Sodium
Na	ⓘ Aegirine	NaFe³⁺Si₂O₆
Na	ⓘ Arfvedsonite	[Na][Na₂][Fe₄²⁺Fe³⁺]Si₈O₂₂(OH)₂
Na	ⓘ Riebeckite	◻[Na₂][Fe₃²⁺Fe₂³⁺]Si₈O₂₂(OH)₂
Al	Aluminium
Al	ⓘ Sanidine	K(AlSi₃O₈)
Si	Silicon
Si	ⓘ Aegirine	NaFe³⁺Si₂O₆
Si	ⓘ Arfvedsonite	[Na][Na₂][Fe₄²⁺Fe³⁺]Si₈O₂₂(OH)₂
Si	ⓘ Quartz	SiO₂
Si	ⓘ Riebeckite	◻[Na₂][Fe₃²⁺Fe₂³⁺]Si₈O₂₂(OH)₂
Si	ⓘ Sanidine	K(AlSi₃O₈)
K	Potassium
K	ⓘ Sanidine	K(AlSi₃O₈)
Fe	Iron
Fe	ⓘ Aegirine	NaFe³⁺Si₂O₆
Fe	ⓘ Arfvedsonite	[Na][Na₂][Fe₄²⁺Fe³⁺]Si₈O₂₂(OH)₂
Fe	ⓘ Magnetite	Fe²⁺Fe₂³⁺O₄
Fe	ⓘ Riebeckite	◻[Na₂][Fe₃²⁺Fe₂³⁺]Si₈O₂₂(OH)₂

Other Regions, Features and Areas containing this locality

AfricaContinent

African PlateTectonic Plate

East Niger Rift basinBasin
Tuareg Shield
- Eastern Hoggar BeltVolcanic Arc

Central AfricaRegion

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References

Garde, G. 1911. Description geologique des regions situees entre le Niger et le Tchad. Thesis, University of Clermont-Ferrand. A. Hermann et Fils, Paris.

BarBeau, J. (1956). Notice explicative sur la feuille Fort-Lamy. Carte géologique de reconnaissance à l’échelle de, 1(1000000). Gouvernement General de l'Afrique Equatoriale Francaise.

Woolley, A. R. (2001) Alkaline Rocks and Carbonatites of the World, Part 3: Africa - Alkaline Rocks and Carbonatites of the World. The Geological Society of London.p.42

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Select Mineral List Type

Mineral List

Rock Types Recorded

Select Rock List Type

Detailed Mineral List:

Gallery:

List of minerals arranged by Strunz 10th Edition classification

List of minerals for each chemical element

Other Regions, Features and Areas containing this locality

References

Hadjer el Khamis, Hadjer-Lamis Region, Chad i
Regional Level Types
Hadjer el Khamis Group of Peaks
Hadjer-Lamis Region Region
Chad Country