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Deeti volcanic cone, Monduli District, Arusha Region, Tanzaniai
Regional Level Types
Deeti volcanic coneVolcanic Cone
Monduli DistrictDistrict
Arusha RegionRegion
TanzaniaCountry

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00462080017396511653680.jpg
Oxo-magnesio-hastingsite

Deeti volcanic cone, Monduli District, Arusha Region, Tanzania
00462080017396511653680.jpg
Oxo-magnesio-hastingsite

Deeti volcanic cone, Monduli District, Arusha Region, Tanzania
00462080017396511653680.jpg
Oxo-magnesio-hastingsite

Deeti volcanic cone, Monduli District, Arusha Region, Tanzania
Latitude & Longitude (WGS84):
2° 50' 31'' South , 36° 0' 52'' East
Latitude & Longitude (decimal):
-2.84202,36.01452
GeoHash:
G#: kz3xgd8up
GRN:
S02E26
Type:
Volcanic Cone
Köppen climate type:
Aw : Tropical savanna, wet
Nearest Settlements:
PlacePopulationDistance
Kiratu19,803 (2018)66.9km
Monduli5,694 (2018)70.2km
Mindat Locality ID:
241165
Long-form identifier:
mindat:1:2:241165:4
GUID (UUID V4):
0


Coordinates from map in Johnson et al (1997)

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


4 valid minerals. 1 (TL) - type locality of valid minerals. 1 erroneous literature entry.

Detailed Mineral List:

ⓘ Diopside
Formula: CaMgSi2O6
Description: Phenocrysts in tuff and inclusions in amphibole
ⓘ Magnesio-hastingsite
Formula: NaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Description: The mineral occurs as megacrysts up to 12 cm in size in crystal-rich tuff. Zaitsev et al. (2013) publish the following empirical formula (Na0.68K0.32)Σ1.00(Ca1.88Na0.12Mn0.02)Σ2.03(Mg2.92Fe2+0.98Fe3+0.55Ti0.49Al0.12)Σ5.06(Al1.97Si6.03O22)(O0.70OH1.30)Σ2.00
ⓘ Oxo-magnesio-hastingsite (TL)
Formula: NaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
Type Locality:
Description: Up to 12 cm phenocrysts in tuff. Chemical composition according to Zaitsev et al. (2013): (Na0.67K0.33)Σ1.00(Ca1.87Na0.14Mn0.01)Σ2.02(Mg3.27[b]Fe3+1.25[/b]Ti0.44Al0.08)Σ5.04(Al1.80Si6.20O22)(O1.40OH0.60)Σ2.00
ⓘ Pargasite
Formula: NaCa2(Mg4Al)(Si6Al2)O22(OH)2
ⓘ Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
Description: Phenocrysts in tuff

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 9 - Silicates
ⓘDiopside9.DA.15CaMgSi2O6
ⓘMagnesio-hastingsite9.DE.15NaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
ⓘPargasite ?9.DE.15NaCa2(Mg4Al)(Si6Al2)O22(OH)2
ⓘOxo-magnesio-hastingsite (TL)9.DE.15NaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
ⓘPhlogopite9.EC.20KMg3(AlSi3O10)(OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ Magnesio-hastingsiteNaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Hⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Hⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
OOxygen
Oⓘ DiopsideCaMgSi2O6
Oⓘ Magnesio-hastingsiteNaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Oⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Oⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Oⓘ Oxo-magnesio-hastingsiteNaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
NaSodium
Naⓘ Magnesio-hastingsiteNaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Naⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Naⓘ Oxo-magnesio-hastingsiteNaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
MgMagnesium
Mgⓘ DiopsideCaMgSi2O6
Mgⓘ Magnesio-hastingsiteNaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Mgⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Mgⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Mgⓘ Oxo-magnesio-hastingsiteNaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
AlAluminium
Alⓘ Magnesio-hastingsiteNaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Alⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Alⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Alⓘ Oxo-magnesio-hastingsiteNaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
SiSilicon
Siⓘ DiopsideCaMgSi2O6
Siⓘ Magnesio-hastingsiteNaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Siⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Siⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Siⓘ Oxo-magnesio-hastingsiteNaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
KPotassium
Kⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
CaCalcium
Caⓘ DiopsideCaMgSi2O6
Caⓘ Magnesio-hastingsiteNaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Caⓘ PargasiteNaCa2(Mg4Al)(Si6Al2)O22(OH)2
Caⓘ Oxo-magnesio-hastingsiteNaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
TiTitanium
Tiⓘ Oxo-magnesio-hastingsiteNaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2
FeIron
Feⓘ Magnesio-hastingsiteNaCa2(Mg4Fe3+)(Si6Al2)O22(OH)2
Feⓘ Oxo-magnesio-hastingsiteNaCa2(Mg3(Fe3+2-x,Tix))5(Si6Al2O22)O2

Other Regions, Features and Areas containing this locality

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.

References

Johnson, L. H., Jones, A. P., Church, A. A., & Taylor, W. R. (1997). Ultramafic xenoliths and megacrysts from a melilitite tuff cone, Deeti, northern Tanzania. Journal of African Earth Sciences, 25(1), 29–42. doi:10.1016/s0899-5362(97)00060-2
Williams, P. A., Hatert, F., Pasero, M., Mills, S. J. (2011) New minerals and nomenclature modifications approved in 2011, CNMNC Newsletter No. 10. Mineralogical Magazine, 75 (5) 2549-2561 doi:10.1180/minmag.2011.075.5.2549
Zaitsev, A. N., Avdontseva, E. Yu., Britvin, S. N., Demény, A., Homonnay, Z., Jeffries, T. E., Keller, J., Krivovichev, V. G., Markl, G., Platonova, N. V., Siidra, O. I., Spratt, J., Vennemann, T. (2013) Oxo-magnesio-hastingsite, NaCa2(Mg2Fe3+3 )(Al2Si6)O22O2, a new anhydrous amphibole from the Deeti volcanic cone, Gregory rift, northern Tanzania. Mineralogical Magazine, 77 (6) 2773-2792 doi:10.1180/minmag.2013.077.6.06
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