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Koidu-Yengema, Kono District, Eastern Province, Sierra Leonei
Regional Level Types
Koidu-YengemaMining Area
Kono DistrictDistrict
Eastern ProvinceProvince
Sierra LeoneCountry

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Latitude & Longitude (WGS84):
8° 37' 50'' North , 10° 58' 20'' West
Latitude & Longitude (decimal):
8.63064,-10.97241
GeoHash:
G#: ec81n74jh
GRN:
N06W08
Type:
Mining Area
Köppen climate type:
Am : Tropical monsoon climate
Mindat Locality ID:
10167
Long-form identifier:
mindat:1:2:10167:6
GUID (UUID V4):
0


A diamond mining area in kimberlite 250 km (~155 miles) east of Freetown.

The mining area is 4km² and comprised of two kimberlite pipes and four dyke zones.

Crustal xenoliths are typically diabase, amphibolites, and granite.

GPS coordinates are for the town of Koidu.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

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


Mineral List


24 valid minerals.

Rock Types Recorded

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

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Almandine
Formula: Fe2+3Al2(SiO4)3
ⓘ 'Amphibole Supergroup'
Formula: AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ 'Apatite'
Formula: Ca5(PO4)3(Cl/F/OH)
ⓘ Calcite
Formula: CaCO3
ⓘ 'Chlorite Group'
ⓘ Corundum
Formula: Al2O3
ⓘ Diamond
Formula: C
ⓘ Diopside
Formula: CaMgSi2O6
ⓘ 'Fayalite-Forsterite Series'
ⓘ Graphite
Formula: C
ⓘ Grossular
Formula: Ca3Al2(SiO4)3
ⓘ Hematite
Formula: Fe2O3
ⓘ Ilmenite
Formula: Fe2+TiO3
ⓘ Jadeite
Formula: Na(Al,Fe3+)Si2O6
ⓘ Kyanite
Formula: Al2(SiO4)O
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Magnetite var. Titanium-bearing Magnetite
Formula: Fe2+(Fe3+,Ti)2O4
ⓘ Native Iron
Formula: Fe
ⓘ Omphacite
Formula: (NaaCabFe2+cMgd)(AleFe3+fFe2+gMgh)Si2O6
ⓘ Perovskite
Formula: CaTiO3
ⓘ Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrope
Formula: Mg3Al2(SiO4)3
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2
ⓘ Rutile
Formula: TiO2
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
ⓘ Titanite
Formula: CaTi(SiO4)O
ⓘ Titanomaghemite
Formula: (Ti4+0.5◻0.5)Fe3+2O4
ⓘ 'UM1985-06-O:CrFeMgTi'
Formula: (Fe2+,Mg,Ti,Cr)6O7
ⓘ Wüstite
Formula: FeO

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Iron1.AE.05Fe
ⓘGraphite1.CB.05aC
ⓘDiamond1.CB.10aC
Group 2 - Sulphides and Sulfosalts
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘWüstite4.AB.25FeO
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘvar. Titanium-bearing Magnetite4.BB.05Fe2+(Fe3+,Ti)2O4
ⓘTitanomaghemite4.BB.15(Ti4+0.5◻0.5)Fe3+2O4
ⓘCorundum4.CB.05Al2O3
ⓘHematite4.CB.05Fe2O3
ⓘIlmenite4.CB.05Fe2+TiO3
ⓘPerovskite4.CC.30CaTiO3
ⓘQuartz4.DA.05SiO2
ⓘRutile4.DB.05TiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘAlmandine9.AD.25Fe2+3Al2(SiO4)3
ⓘGrossular9.AD.25Ca3Al2(SiO4)3
ⓘPyrope9.AD.25Mg3Al2(SiO4)3
ⓘKyanite9.AF.15Al2(SiO4)O
ⓘTitanite9.AG.15CaTi(SiO4)O
ⓘDiopside9.DA.15CaMgSi2O6
ⓘOmphacite9.DA.20(NaaCabFe2+cMgd)(AleFe3+fFe2+gMgh)Si2O6
ⓘJadeite9.DA.25Na(Al,Fe3+)Si2O6
ⓘPhlogopite9.EC.20KMg3(AlSi3O10)(OH)2
Unclassified
ⓘ'Amphibole Supergroup'-AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ'Chlorite Group'-
ⓘ'Fayalite-Forsterite Series'-
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4
ⓘ'Apatite'-Ca5(PO4)3(Cl/F/OH)
ⓘ'UM1985-06-O:CrFeMgTi'-(Fe2+,Mg,Ti,Cr)6O7

List of minerals for each chemical element

HHydrogen
Hⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Hⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
Hⓘ ApatiteCa5(PO4)3(Cl/F/OH)
CCarbon
Cⓘ CalciteCaCO3
Cⓘ DiamondC
Cⓘ GraphiteC
OOxygen
Oⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Oⓘ AlmandineFe32+Al2(SiO4)3
Oⓘ CalciteCaCO3
Oⓘ CorundumAl2O3
Oⓘ DiopsideCaMgSi2O6
Oⓘ GrossularCa3Al2(SiO4)3
Oⓘ HematiteFe2O3
Oⓘ IlmeniteFe2+TiO3
Oⓘ JadeiteNa(Al,Fe3+)Si2O6
Oⓘ KyaniteAl2(SiO4)O
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ Omphacite(NaaCabFec2+Mgd)(AleFef3+Feg2+Mgh)Si2O6
Oⓘ PerovskiteCaTiO3
Oⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Oⓘ PyropeMg3Al2(SiO4)3
Oⓘ QuartzSiO2
Oⓘ RutileTiO2
Oⓘ TitaniteCaTi(SiO4)O
Oⓘ Magnetite var. Titanium-bearing MagnetiteFe2+(Fe3+,Ti)2O4
Oⓘ WüstiteFeO
Oⓘ Fayalite-Forsterite Series
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
Oⓘ Titanomaghemite(Ti4+0.5◻0.5)Fe23+O4
Oⓘ ApatiteCa5(PO4)3(Cl/F/OH)
Oⓘ UM1985-06-O:CrFeMgTi(Fe2+,Mg,Ti,Cr)6O7
FFluorine
Fⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Fⓘ ApatiteCa5(PO4)3(Cl/F/OH)
NaSodium
Naⓘ JadeiteNa(Al,Fe3+)Si2O6
Naⓘ Omphacite(NaaCabFec2+Mgd)(AleFef3+Feg2+Mgh)Si2O6
MgMagnesium
Mgⓘ DiopsideCaMgSi2O6
Mgⓘ Omphacite(NaaCabFec2+Mgd)(AleFef3+Feg2+Mgh)Si2O6
Mgⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Mgⓘ PyropeMg3Al2(SiO4)3
Mgⓘ Fayalite-Forsterite Series
Mgⓘ UM1985-06-O:CrFeMgTi(Fe2+,Mg,Ti,Cr)6O7
AlAluminium
Alⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Alⓘ AlmandineFe32+Al2(SiO4)3
Alⓘ CorundumAl2O3
Alⓘ GrossularCa3Al2(SiO4)3
Alⓘ JadeiteNa(Al,Fe3+)Si2O6
Alⓘ KyaniteAl2(SiO4)O
Alⓘ Omphacite(NaaCabFec2+Mgd)(AleFef3+Feg2+Mgh)Si2O6
Alⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Alⓘ PyropeMg3Al2(SiO4)3
SiSilicon
Siⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Siⓘ AlmandineFe32+Al2(SiO4)3
Siⓘ DiopsideCaMgSi2O6
Siⓘ GrossularCa3Al2(SiO4)3
Siⓘ JadeiteNa(Al,Fe3+)Si2O6
Siⓘ KyaniteAl2(SiO4)O
Siⓘ Omphacite(NaaCabFec2+Mgd)(AleFef3+Feg2+Mgh)Si2O6
Siⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Siⓘ PyropeMg3Al2(SiO4)3
Siⓘ QuartzSiO2
Siⓘ TitaniteCaTi(SiO4)O
Siⓘ Fayalite-Forsterite Series
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
PPhosphorus
Pⓘ ApatiteCa5(PO4)3(Cl/F/OH)
SSulfur
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
ClChlorine
Clⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Clⓘ ApatiteCa5(PO4)3(Cl/F/OH)
KPotassium
Kⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ DiopsideCaMgSi2O6
Caⓘ GrossularCa3Al2(SiO4)3
Caⓘ Omphacite(NaaCabFec2+Mgd)(AleFef3+Feg2+Mgh)Si2O6
Caⓘ PerovskiteCaTiO3
Caⓘ TitaniteCaTi(SiO4)O
Caⓘ ApatiteCa5(PO4)3(Cl/F/OH)
TiTitanium
Tiⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Tiⓘ IlmeniteFe2+TiO3
Tiⓘ PerovskiteCaTiO3
Tiⓘ RutileTiO2
Tiⓘ TitaniteCaTi(SiO4)O
Tiⓘ Magnetite var. Titanium-bearing MagnetiteFe2+(Fe3+,Ti)2O4
Tiⓘ Titanomaghemite(Ti4+0.5◻0.5)Fe23+O4
Tiⓘ UM1985-06-O:CrFeMgTi(Fe2+,Mg,Ti,Cr)6O7
CrChromium
Crⓘ UM1985-06-O:CrFeMgTi(Fe2+,Mg,Ti,Cr)6O7
FeIron
Feⓘ AlmandineFe32+Al2(SiO4)3
Feⓘ HematiteFe2O3
Feⓘ IlmeniteFe2+TiO3
Feⓘ Native IronFe
Feⓘ JadeiteNa(Al,Fe3+)Si2O6
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ Omphacite(NaaCabFec2+Mgd)(AleFef3+Feg2+Mgh)Si2O6
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
Feⓘ Magnetite var. Titanium-bearing MagnetiteFe2+(Fe3+,Ti)2O4
Feⓘ WüstiteFeO
Feⓘ Fayalite-Forsterite Series
Feⓘ Titanomaghemite(Ti4+0.5◻0.5)Fe23+O4
Feⓘ UM1985-06-O:CrFeMgTi(Fe2+,Mg,Ti,Cr)6O7

Other Regions, Features and Areas containing this locality

AfricaContinent
African PlateTectonic Plate
West AfricaUN Subregion

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

en.wikipedia.org (n.d.) https://en.wikipedia.org/wiki/Koidu
en.wikipedia.org (n.d.) https://en.wikipedia.org/wiki/Yengema
Hills, Doris V., Haggerty, Stephen E. (1989) Petrochemistry of eclogites from the Koidu Kimberlite Complex, Sierra Leone. Contributions to Mineralogy and Petrology, 103 (4) 397-422 doi:10.1007/bf01041749
Haggerty, S. E., Hargraves, R. B., & Tompkins, L. A. (1990). Oxide mineralogy and magnetic properties of the Koidu kimberlite complex, Sierra Leone, west Africa. Geophysical Journal International, 100(2), 275-283.
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