Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Alto Alentejo Complex, Monforte, Portalegre, Portugali
Regional Level Types
Alto Alentejo ComplexComplex
MonforteMunicipality
PortalegreDistrict
PortugalCountry

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Latitude & Longitude (WGS84):
39° 4' 42'' North , 7° 1' 58'' West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~0km
Type:
Age:
466 ± 12 Ma
Geologic Time:
Dating method:
Rb-Sr whole rock
Reference for age:
Priem, H. N. A., Boelrijk, N. A. I. M., Verschure, R. H., Hebeda, E. H., & Verdurmen, E. T. (1970). Dating events of acid plutonism through the Paleozoic of the Western Iberian Peninsula. Eclogae Geologicae Helvetiae, 63(1), 255-274.
Mindat Locality ID:
388109
Long-form identifier:
mindat:1:2:388109:8
GUID (UUID V4):
0


In an area c. 60 x 40 km, trending NW-SE including towns and villages of Alter do Chão, Monforte, Arronches, Ouguela, Campo Maior and Elvas are a series of Lower Paleozoic peralkaline syenites, granites, granite gneisses and rare nepheline syenite gneisses, which were deformed and partly recrystallized in the Hercynian orogeny (Teixeira & Assunção 1957; Assunção & Gonçalves 1971). The country rocks are principally Precambrian and Cambrian metamorphic rocks with major basic, ultrabasic and granite intrusions.

The largest single occurrence extends for 28 km between Alter do Chão and Monforte and varies in thickness from a few hundred meters to 2 km and over.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

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

16 valid minerals.

Rock Types Recorded


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

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

Aegirine
Formula: NaFe3+Si2O6
Aegirine-augite
Formula: (NaaCabFe2+cMgd)(Fe3+eAlfFe2+gMgh)Si2O6
References:
Aenigmatite
Formula: Na4[Fe2+10Ti2]O4[Si12O36]
References:
Albite
Formula: Na(AlSi3O8)
Augite
Formula: (CaxMgyFez)(Mgy1Fez1)Si2O6
References:
'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Cancrinite
Formula: (Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
Fluorite
Formula: CaF2
References:
'Garnet Group'
Formula: X3Z2(SiO4)3
Magnetite
Formula: Fe2+Fe3+2O4
References:
Microcline
Formula: K(AlSi3O8)
Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Nepheline
Formula: Na3K(Al4Si4O16)
Quartz
Formula: SiO2
References:
Riebeckite
Formula: ◻Na2(Fe2+3Fe3+2)Si8O22(OH)2
Sodalite
Formula: Na4(Si3Al3)O12Cl
'Sodic amphibole'
References:
Titanite
Formula: CaTi(SiO4)O
Zircon
Formula: Zr(SiO4)

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 3 - Halides
Fluorite3.AB.25CaF2
Group 4 - Oxides and Hydroxides
Magnetite4.BB.05Fe2+Fe3+2O4
Quartz4.DA.05SiO2
Group 9 - Silicates
Zircon9.AD.30Zr(SiO4)
Titanite9.AG.15CaTi(SiO4)O
Augite9.DA.15(CaxMgyFez)(Mgy1Fez1)Si2O6
Aegirine-augite9.DA.20(NaaCabFe2+cMgd)(Fe3+eAlfFe2+gMgh)Si2O6
Aegirine9.DA.25NaFe3+Si2O6
Riebeckite9.DE.25◻Na2(Fe2+3Fe3+2)Si8O22(OH)2
Aenigmatite9.DH.40Na4[Fe2+10Ti2]O4[Si12O36]
Muscovite9.EC.15KAl2(AlSi3O10)(OH)2
Nepheline9.FA.05Na3K(Al4Si4O16)
Microcline9.FA.30K(AlSi3O8)
Albite9.FA.35Na(AlSi3O8)
Cancrinite9.FB.05(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
Sodalite9.FB.10Na4(Si3Al3)O12Cl
Unclassified
'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
'Garnet Group'-X3Z2(SiO4)3
'Sodic amphibole'-

List of minerals for each chemical element

HHydrogen
H BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
H Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
H MuscoviteKAl2(AlSi3O10)(OH)2
H Riebeckite◻Na2(Fe32+Fe23+)Si8O22(OH)2
CCarbon
C Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
OOxygen
O AegirineNaFe3+Si2O6
O Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
O AenigmatiteNa4[Fe102+Ti2]O4[Si12O36]
O AlbiteNa(AlSi3O8)
O Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
O BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
O Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
O MagnetiteFe2+Fe23+O4
O MicroclineK(AlSi3O8)
O MuscoviteKAl2(AlSi3O10)(OH)2
O NephelineNa3K(Al4Si4O16)
O QuartzSiO2
O Riebeckite◻Na2(Fe32+Fe23+)Si8O22(OH)2
O SodaliteNa4(Si3Al3)O12Cl
O TitaniteCaTi(SiO4)O
O ZirconZr(SiO4)
O Garnet GroupX3Z2(SiO4)3
FFluorine
F BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
F FluoriteCaF2
NaSodium
Na AegirineNaFe3+Si2O6
Na Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Na AenigmatiteNa4[Fe102+Ti2]O4[Si12O36]
Na AlbiteNa(AlSi3O8)
Na Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
Na NephelineNa3K(Al4Si4O16)
Na Riebeckite◻Na2(Fe32+Fe23+)Si8O22(OH)2
Na SodaliteNa4(Si3Al3)O12Cl
MgMagnesium
Mg Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Mg Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Mg BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Al Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Al AlbiteNa(AlSi3O8)
Al BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Al Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
Al MicroclineK(AlSi3O8)
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al NephelineNa3K(Al4Si4O16)
Al SodaliteNa4(Si3Al3)O12Cl
SiSilicon
Si AegirineNaFe3+Si2O6
Si Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Si AenigmatiteNa4[Fe102+Ti2]O4[Si12O36]
Si AlbiteNa(AlSi3O8)
Si Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Si BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Si Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
Si MicroclineK(AlSi3O8)
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si NephelineNa3K(Al4Si4O16)
Si QuartzSiO2
Si Riebeckite◻Na2(Fe32+Fe23+)Si8O22(OH)2
Si SodaliteNa4(Si3Al3)O12Cl
Si TitaniteCaTi(SiO4)O
Si ZirconZr(SiO4)
Si Garnet GroupX3Z2(SiO4)3
SSulfur
S Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
ClChlorine
Cl SodaliteNa4(Si3Al3)O12Cl
KPotassium
K BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
K MicroclineK(AlSi3O8)
K MuscoviteKAl2(AlSi3O10)(OH)2
K NephelineNa3K(Al4Si4O16)
CaCalcium
Ca Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Ca Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Ca Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2O
Ca FluoriteCaF2
Ca TitaniteCaTi(SiO4)O
TiTitanium
Ti AenigmatiteNa4[Fe102+Ti2]O4[Si12O36]
Ti BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Ti TitaniteCaTi(SiO4)O
FeIron
Fe AegirineNaFe3+Si2O6
Fe Aegirine-augite(NaaCabFec2+Mgd)(Fee3+AlfFeg2+Mgh)Si2O6
Fe AenigmatiteNa4[Fe102+Ti2]O4[Si12O36]
Fe Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Fe BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fe MagnetiteFe2+Fe23+O4
Fe Riebeckite◻Na2(Fe32+Fe23+)Si8O22(OH)2
ZrZirconium
Zr ZirconZr(SiO4)

Localities in this Region

Other Regions, Features and Areas that Intersect

Eurasian PlateTectonic Plate
EuropeContinent

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