100 kilometre long volcanic field in elongated NW-SE direction.
Pleistocene Northern Chyulu Hills lavas and the Holocene Southern Chyulu Hills lavas.

Guano was mined in lave tubes (lava caves).

Age: Lower Pleistocene to Recent. Dating of a sample of carbon from beneath the lava flow gave 480±200 years (Saggerson 1963).

Approx. coordinates range: 2º00' - 2º45'S; 37º30' - 38º20'E.

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Standard Detailed Gallery Strunz Chemical Elements

Mineral List

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

10 valid minerals.

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

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Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Analcime

Formula: Na(AlSi₂O₆) · H₂O

References:

Searle, D. L. (1954). Geology of the Sultan Hamud area. Report, Geological Survey of Kenya, 29.

Saggerson, E. P. (1963). Geology of the Simba-Kibwezi area. Geological Survey of Kenya, 58, 70.

Goles, G. G. (1975). Basalts of unusual composition from the Chyulu Hills, Kenya. Lithos, 8(1), 47-58.

HENJES-KUNST, F., ALTHERR, R. (1992) Metamorphic Petrology of Xenoliths from Kenya and Northern Tanzania and Implications for Geotherms and Lithospheric Structures. Journal of Petrology, 33 (5) 1125-1156 doi:10.1093/petrology/33.5.1125

ⓘ 'Apatite'

Formula: Ca₅(PO₄)₃(Cl/F/OH)

References:

Späth, A., Le Roex, A.P., Opiyo-Akech, N. (2001) Plume–lithosphere interaction and the origin of continental rift-related alkaline volcanism—the Chyulu Hills Volcanic Province, southern Kenya. Journal of Petrology, 42:4, 765-787.

ⓘ Bobierrite

Formula: Mg₃(PO₄)₂ · 8H₂O

Locality: Imperial Canyon Lava tubes, Chyulu Hills, Makueni County, Kenya

References:

Mineralogical Society of America - Handbook of Mineralogy

ⓘ 'Chrome-Spinel (of Dana)'

References:

ⓘ 'Clinopyroxene Subgroup'

References:

Ulianov, A., Kalt, A., Pettke, T. (2005) Hibonite, Ca (Al, Cr, Ti, Si, Mg, Fe2+)12 O19, in granulite xenoliths from the Chyulu Hills volcanic field, Kenya. European Journal of Mineralogy, 17:2, 343-356.

ⓘ 'Fayalite-Forsterite Series'

References:

ⓘ Gypsum

Formula: CaSO₄ · 2H₂O

Locality: Mathaioni Cave, Chyulu Hills, Makueni County, Kenya

References:

Forti, P., Galli, E., & Rossi, A. (2003) Minerogenesis of volcanic caves of Kenya. International Journal of Speleology, 32(1), 1.

ⓘ Hibonite

Formula: CaAl₁₂O₁₉

References:

ⓘ Mullite

Formula: Al_4+2xSi_2-2xO_10-x

References:

ⓘ Nepheline

Formula: Na₃K(Al₄Si₄O₁₆)

References:

Searle, D. L. (1954). Geology of the Sultan Hamud area. Report, Geological Survey of Kenya, 29.

Saggerson, E. P. (1963). Geology of the Simba-Kibwezi area. Geological Survey of Kenya, 58, 70.

Goles, G. G. (1975). Basalts of unusual composition from the Chyulu Hills, Kenya. Lithos, 8(1), 47-58.

ⓘ Opal

Formula: SiO₂ · nH₂O

Locality: Leviathan Cave, Chyulu Hills, Makueni County, Kenya

References:

Forti, P., Galli, E., & Rossi, A. (2003) Minerogenesis of volcanic caves of Kenya. International Journal of Speleology, 32(1), 1.

ⓘ 'Plagioclase'

Formula: (Na,Ca)[(Si,Al)AlSi₂]O₈

References:

Späth, A., Le Roex, A.P., Opiyo-Akech, N. (2000) The petrology of the Chyulu Hills Volcanic Province, southern Kenya. Journal of African Earth Sciences, 31:2, 337-358.

ⓘ Sapphirine

Formula: Mg₄(Mg₃Al₉)O₄[Si₃Al₉O₃₆]

References:

ⓘ Sillimanite

Formula: Al₂(SiO₄)O

References:

ⓘ Spinel

Formula: MgAl₂O₄

References:

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘ	Spinel	4.BB.05	MgAl₂O₄
ⓘ	Hibonite	4.CC.45	CaAl₁₂O₁₉
ⓘ	Opal	4.DA.10	SiO₂ · nH₂O
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘ	Gypsum	7.CD.40	CaSO₄ · 2H₂O
Group 8 - Phosphates, Arsenates and Vanadates
ⓘ	Bobierrite	8.CE.35	Mg₃(PO₄)₂ · 8H₂O
Group 9 - Silicates
ⓘ	Sillimanite	9.AF.05	Al₂(SiO₄)O
ⓘ	Mullite	9.AF.20	Al_4+2xSi_2-2xO_10-x
ⓘ	Sapphirine	9.DH.45	Mg₄(Mg₃Al₉)O₄[Si₃Al₉O₃₆]
ⓘ	Nepheline	9.FA.05	Na₃K(Al₄Si₄O₁₆)
ⓘ	Analcime	9.GB.05	Na(AlSi₂O₆) · H₂O
Unclassified
ⓘ	'Clinopyroxene Subgroup'	-
ⓘ	'Fayalite-Forsterite Series'	-
ⓘ	'Plagioclase'	-	(Na,Ca)[(Si,Al)AlSi₂]O₈
ⓘ	'Chrome-Spinel (of Dana)'	-
ⓘ	'Apatite'	-	Ca₅(PO₄)₃(Cl/F/OH)

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
H	ⓘ Bobierrite	Mg₃(PO₄)₂ · 8H₂O
H	ⓘ Gypsum	CaSO₄ · 2H₂O
H	ⓘ Opal	SiO₂ · nH₂O
H	ⓘ Apatite	Ca₅(PO₄)₃(Cl/F/OH)
O	Oxygen
O	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
O	ⓘ Bobierrite	Mg₃(PO₄)₂ · 8H₂O
O	ⓘ Gypsum	CaSO₄ · 2H₂O
O	ⓘ Hibonite	CaAl₁₂O₁₉
O	ⓘ Mullite	Al_4+2xSi_2-2xO_10-x
O	ⓘ Nepheline	Na₃K(Al₄Si₄O₁₆)
O	ⓘ Opal	SiO₂ · nH₂O
O	ⓘ Sapphirine	Mg₄(Mg₃Al₉)O₄[Si₃Al₉O₃₆]
O	ⓘ Sillimanite	Al₂(SiO₄)O
O	ⓘ Spinel	MgAl₂O₄
O	ⓘ Fayalite-Forsterite Series
O	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
O	ⓘ Apatite	Ca₅(PO₄)₃(Cl/F/OH)
F	Fluorine
F	ⓘ Apatite	Ca₅(PO₄)₃(Cl/F/OH)
Na	Sodium
Na	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Na	ⓘ Nepheline	Na₃K(Al₄Si₄O₁₆)
Na	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
Mg	Magnesium
Mg	ⓘ Bobierrite	Mg₃(PO₄)₂ · 8H₂O
Mg	ⓘ Sapphirine	Mg₄(Mg₃Al₉)O₄[Si₃Al₉O₃₆]
Mg	ⓘ Spinel	MgAl₂O₄
Mg	ⓘ Fayalite-Forsterite Series
Al	Aluminium
Al	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Al	ⓘ Hibonite	CaAl₁₂O₁₉
Al	ⓘ Mullite	Al_4+2xSi_2-2xO_10-x
Al	ⓘ Nepheline	Na₃K(Al₄Si₄O₁₆)
Al	ⓘ Sapphirine	Mg₄(Mg₃Al₉)O₄[Si₃Al₉O₃₆]
Al	ⓘ Sillimanite	Al₂(SiO₄)O
Al	ⓘ Spinel	MgAl₂O₄
Al	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
Si	Silicon
Si	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Si	ⓘ Mullite	Al_4+2xSi_2-2xO_10-x
Si	ⓘ Nepheline	Na₃K(Al₄Si₄O₁₆)
Si	ⓘ Opal	SiO₂ · nH₂O
Si	ⓘ Sapphirine	Mg₄(Mg₃Al₉)O₄[Si₃Al₉O₃₆]
Si	ⓘ Sillimanite	Al₂(SiO₄)O
Si	ⓘ Fayalite-Forsterite Series
Si	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
P	Phosphorus
P	ⓘ Bobierrite	Mg₃(PO₄)₂ · 8H₂O
P	ⓘ Apatite	Ca₅(PO₄)₃(Cl/F/OH)
S	Sulfur
S	ⓘ Gypsum	CaSO₄ · 2H₂O
Cl	Chlorine
Cl	ⓘ Apatite	Ca₅(PO₄)₃(Cl/F/OH)
K	Potassium
K	ⓘ Nepheline	Na₃K(Al₄Si₄O₁₆)
Ca	Calcium
Ca	ⓘ Gypsum	CaSO₄ · 2H₂O
Ca	ⓘ Hibonite	CaAl₁₂O₁₉
Ca	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
Ca	ⓘ Apatite	Ca₅(PO₄)₃(Cl/F/OH)
Fe	Iron
Fe	ⓘ Fayalite-Forsterite Series

Other Databases

Wikipedia:	https://en.wikipedia.org/wiki/Chyulu_Hills
Wikidata ID:	Q5118629

Localities in this Region

Kenya

Makueni County
- Chyulu Hills

Other Regions, Features and Areas containing this locality

AfricaContinent

East African Rift System (EARS)Zone (Tectonic)

African Plate

Tanzanian Eastern GranulitesOrogenic Belt

Kenya

⭔Eastern 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

doi.org/10.1016/0024-4937(75)90030-4

Mineralogical Society of America - Handbook of Mineralogy

Searle, D. L. (1954). Geology of the Sultan Hamud area. Report, Geological Survey of Kenya, 29.

Saggerson, E. P. (1963). Geology of the Simba-Kibwezi area. Geological Survey of Kenya, 58, 70.

Goles, G. G. (1975). Basalts of unusual composition from the Chyulu Hills, Kenya. Lithos, 8(1), 47-58.

Simons, Jim (1998) Guano mining in Kenyan lava tunnel caves. International Journal of Speleology, 27 (1). 33-51 doi:10.5038/1827-806x.27.1.4

Späth, A., Le Roex, A.P., Opiyo-Akech, N. (2000) The petrology of the Chyulu Hills Volcanic Province, southern Kenya. Journal of African Earth Sciences, 31:2, 337-358.

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Chyulu Hills, Makueni County, KenyaiRegional Level TypesChyulu HillsGroup of Hills Makueni CountyDistrict KenyaCountry function showexplain() { $("#locexplain").toggle(); if (typeof movemap === "function") movemap(); }

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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 Databases

Localities in this Region

Other Regions, Features and Areas containing this locality

References

Chyulu Hills, Makueni County, Kenya i
Regional Level Types
Chyulu Hills Group of Hills
Makueni County District
Kenya Country