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Gralheira Mine, Alfarela de Jales, Vila Pouca de Aguiar, Vila Real, Portugali
Regional Level Types
Gralheira MineMine
Alfarela de JalesCivil Parish
Vila Pouca de AguiarMunicipality
Vila RealDistrict
PortugalCountry

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Latitude & Longitude (WGS84):
41° 28' 4'' North , 7° 33' 24'' West
Latitude & Longitude (decimal):
41.46791,-7.55691
GeoHash:
G#: ez6euj10p
GRN:
N28W05
Type:
Mine
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Sobreira4,219 (2018)21.4km
Sabrosa6,361 (2018)22.4km
Alijó11,942 (2018)22.5km
Favaios1,064 (2018)22.6km
Vila Real17,001 (2012)24.3km
Mindat Locality ID:
244806
Long-form identifier:
mindat:1:2:244806:3
GUID (UUID V4):
0
Name(s) in local language(s):
Mina da Gralheira, Alfarela de Jales, Vila Pouca de Aguiar, Distrito de Vila Real, Portugal


Roman gold mine.

Quartz lenses and veins within Ordovician schists.

Two mining concessions included in the Jales mining field:
1884 Gralheira no. 1 (W-Sn-Au-Ag), registered on 02-03-1935
1885 Gralheira no. 2 (W-Sn-Au-Ag), registered on 04-03-1935

The WNW-​ESE-​trending hydrothermal gold-​quartz veins at Gralheira in northern Portugal cut alternating mica schists and quartzites of mainly Ordovician age and, to the west, also cut a Hercynian muscovite-​biotite granite. The veins have been prospected and developed to a depth of 300 m.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


22 valid minerals.

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ Arsenopyrite
Formula: FeAsS
ⓘ Boulangerite
Formula: Pb5Sb4S11
ⓘ Calcite
Formula: CaCO3
ⓘ Cassiterite
Formula: SnO2
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ 'Chlorite Group'
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ 'Freibergite Subgroup'
Formula: (Ag6,[Ag6]4+)(Cu4 C2+2)Sb4S12S0-1
ⓘ Galena
Formula: PbS
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Marcasite
Formula: FeS2
ⓘ 'Mica Group'
ⓘ Microcline
Formula: K(AlSi3O8)
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Native Bismuth
Formula: Bi
ⓘ Native Gold
Formula: Au
ⓘ Native Gold var. Electrum
Formula: (Au,Ag)
ⓘ Native Silver
Formula: Ag
ⓘ Owyheeite
Formula: Ag3Pb10Sb11S28
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2
ⓘ Rutile
Formula: TiO2
ⓘ Sphalerite
Formula: ZnS
ⓘ 'Tetrahedrite Subgroup'
Formula: Cu6(Cu4C2+2)Sb4S12S
ⓘ 'Tourmaline'
Formula: AD3G6 (T6O18)(BO3)3X3Z
ⓘ 'Wolframite Group'
ⓘ Zircon
Formula: Zr(SiO4)

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Gold
var. Electrum		1.AA.05(Au,Ag)
ⓘ1.AA.05Au
ⓘNative Silver1.AA.05Ag
ⓘNative Bismuth1.CA.05Bi
Group 2 - Sulphides and Sulfosalts
ⓘSphalerite2.CB.05aZnS
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘGalena2.CD.10PbS
ⓘPyrite2.EB.05aFeS2
ⓘMarcasite2.EB.10aFeS2
ⓘArsenopyrite2.EB.20FeAsS
ⓘ'Freibergite Subgroup'2.GB.05(Ag6,[Ag6]4+)(Cu4 C2+2)Sb4S12S0-1
ⓘ'Tetrahedrite Subgroup'2.GB.05Cu6(Cu4C2+2)Sb4S12S
ⓘBoulangerite2.HC.15Pb5Sb4S11
ⓘOwyheeite2.HC.35Ag3Pb10Sb11S28
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz4.DA.05SiO2
ⓘCassiterite4.DB.05SnO2
ⓘRutile4.DB.05TiO2
ⓘ'Wolframite Group'4.DB.30 va
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘDolomite5.AB.10CaMg(CO3)2
Group 9 - Silicates
ⓘZircon9.AD.30Zr(SiO4)
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘMicrocline9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
Unclassified
ⓘ'Chlorite Group'-
ⓘ'Tourmaline'-AD3G6 (T6O18)(BO3)3X3Z
ⓘ'Mica Group'-

List of minerals for each chemical element

HHydrogen
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
BBoron
Bⓘ TourmalineAD3G6 (T6O18)(BO3)3X3Z
CCarbon
Cⓘ CalciteCaCO3
Cⓘ DolomiteCaMg(CO3)2
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ CalciteCaCO3
Oⓘ CassiteriteSnO2
Oⓘ DolomiteCaMg(CO3)2
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MicroclineK(AlSi3O8)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ RutileTiO2
Oⓘ TourmalineAD3G6 (T6O18)(BO3)3X3Z
Oⓘ ZirconZr(SiO4)
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
MgMagnesium
Mgⓘ DolomiteCaMg(CO3)2
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ MicroclineK(AlSi3O8)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ MicroclineK(AlSi3O8)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ ZirconZr(SiO4)
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SSulfur
Sⓘ ArsenopyriteFeAsS
Sⓘ BoulangeritePb5Sb4S11
Sⓘ ChalcopyriteCuFeS2
Sⓘ Freibergite Subgroup(Ag6,[Ag6]4+)(Cu4 C22+)Sb4S12S0-1
Sⓘ GalenaPbS
Sⓘ MarcasiteFeS2
Sⓘ OwyheeiteAg3Pb10Sb11S28
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
Sⓘ SphaleriteZnS
Sⓘ Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
KPotassium
Kⓘ MicroclineK(AlSi3O8)
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ DolomiteCaMg(CO3)2
TiTitanium
Tiⓘ RutileTiO2
FeIron
Feⓘ ArsenopyriteFeAsS
Feⓘ ChalcopyriteCuFeS2
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ MarcasiteFeS2
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
CuCopper
Cuⓘ ChalcopyriteCuFeS2
Cuⓘ Freibergite Subgroup(Ag6,[Ag6]4+)(Cu4 C22+)Sb4S12S0-1
Cuⓘ Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
ZnZinc
Znⓘ SphaleriteZnS
AsArsenic
Asⓘ ArsenopyriteFeAsS
ZrZirconium
Zrⓘ ZirconZr(SiO4)
AgSilver
Agⓘ Native Gold var. Electrum(Au,Ag)
Agⓘ Freibergite Subgroup(Ag6,[Ag6]4+)(Cu4 C22+)Sb4S12S0-1
Agⓘ OwyheeiteAg3Pb10Sb11S28
Agⓘ Native SilverAg
SnTin
Snⓘ CassiteriteSnO2
SbAntimony
Sbⓘ BoulangeritePb5Sb4S11
Sbⓘ Freibergite Subgroup(Ag6,[Ag6]4+)(Cu4 C22+)Sb4S12S0-1
Sbⓘ OwyheeiteAg3Pb10Sb11S28
Sbⓘ Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
AuGold
Auⓘ Native Gold var. Electrum(Au,Ag)
Auⓘ Native GoldAu
PbLead
Pbⓘ BoulangeritePb5Sb4S11
Pbⓘ GalenaPbS
Pbⓘ OwyheeiteAg3Pb10Sb11S28
BiBismuth
Biⓘ Native BismuthBi

Other Regions, Features and Areas containing this locality

Eurasian PlateTectonic Plate
EuropeContinent
Iberian PeninsulaPeninsula

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

Neiva, A. M. R. (1994): Gold-​quartz veins at Gralheira, northern Portugal: mineralogical and geochemical characteristics. Transactions of the Institution of Mining and Metallurgy, Section B: Applied Earth Science 103, B188-B196.
Wahl-Clerici, R., Wiechowski, A., Helfert, M. & Ramminger, B. (2012): Die Golderzaufbereitung im römischen Bergwerksbezirk von Três Minas und Campo de Jales in Nordportugal. Der Anschnitt 64, 109-118.
www.medgoldresources.com (n.d.) http://www.medgoldresources.com/boticas.asp
Martins, S. A. B. (2018). Mineralizações auríferas de Jales, Gralheira e Raiz do Monte: estudo mineralógico e paragenético. o Mestrado em Geologia da Faculdade de Ciências da Universidade do Porto
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