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Poggio Mortaio (Poggio Mortaio Mine; Monte Argentario Mine; Poggio delle Polveriere; Terra Rossa; Il Passo), Monte Argentario, Grosseto Province, Tuscany, Italyi
Regional Level Types
Poggio Mortaio (Poggio Mortaio Mine; Monte Argentario Mine; Poggio delle Polveriere; Terra Rossa; Il Passo)Mine (Abandoned)
Monte ArgentarioCommune
Grosseto ProvinceProvince
TuscanyRegion
ItalyCountry

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Latitude & Longitude (WGS84):
42° 24' 51'' North , 11° 11' 54'' East
Latitude & Longitude (decimal):
Type:
Mine (Abandoned) - last checked 2025
Nearest Settlements:
PlacePopulationDistance
Porto Ercole2,676 (2014)1.5km
Orbetello5,779 (2014)3.6km
Giannella225 (2014)3.6km
Orbetello Scalo1,532 (2014)5.7km
Monte Argentario12,147 (2012)6.9km
Mindat Locality ID:
29669
Long-form identifier:
mindat:1:2:29669:1
GUID (UUID V4):
0
Name(s) in local language(s):
Poggio Mortaio (Miniera di Poggio Mortaio; Miniera di Monte Argentario; Poggio delle Polveriere; Terra Rossa; Il Passo), Monte Argentario, Provincia di Grosseto, Toscana, Italia


Old mining area for Fe-Mn ores at Poggio Mortaio (the locality of the Fe-Mn deposit is also known as Poggio delle Polveriere; Terra Rossa; Il Passo), on the NE slope of Monte Argentario, near Orbetello.

Ore mineralisations occur at the contact between Calcare Cavernoso and phyllitic rocks of the Monticiano-Roccastrada unit (Tuscan Verrucano). The Fe-Mn deposit (consisting of limonite, hematite, and manganese oxides), exploited in the period 1874-1958, occurs in the upper part of the Calcare Cavernoso formation, while large unexploited ore deposits occur at deeper levels: a Zn-Pb-Fe mineralised horizon, at a depth of 100-120 m below sea level, in the middle and lower part of the Calcare Cavernoso formation and a pyrite-magnatite body, between 192 and 400 m below sea level, at the contact with the schists.


The Fe-Mn deposit, discovered at Terra Rossa (Terrarossa) in 1873, was initially exploited during the period from 1874 to 1911 by the company Fratelli Rae of Livorno. Operations ceased when the groundwater table was reached, due to difficulty in draining the underground works. Mining was restarted in 1916 by the siderurgical enterprise Ilva, which exploited four main ore masses (named Elena, Guglielmo, Enrico, and Massa No. 1) embedded in limestone. In 1939 the mining concession was transferred to the company Ferromin, which continued operations until 1944, when heavy bombings on Porto Santo Stefano seriously damaged the mining infrastructure. The post-war period saw a new development of the mine and the maximum annual production (40,000 tons of ore) was reached in 1952. Two shafts and various gallery were excavated in this period. Furthermore, geological and mining investigations performed in the 1950s revealed the presence of deeper ore bodies, consisting of mixed sulfides and pyrite-magnetite. In 1958 operations at the mine ceased, mainly because of a significant impairment of the Fe-Mn ore quality (due to the presence of Zn and fine-grained clay). Further exploration works on the Zn-Pb-Fe and pyrite-magnetite deposits were performed during the 1960s by the companies Società Mineraria dell'Argentario and Società Monte Amiata.

Thirteen mineral species have been recently identified from specimens of the Fe-Mn mineralisation (Biagioni et al., 2016). These specimens were collected at the beginning of the 1990s on a dump, located in the area where a luxury residence now stands.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


20 valid minerals.

Detailed Mineral List:

ⓘ Aragonite
Formula: CaCO3
ⓘ Baryte
Formula: BaSO4
ⓘ Beudantite
Formula: PbFe3+3(AsO4)(SO4)(OH)6
ⓘ Calcite
Formula: CaCO3
ⓘ Chalcanthite
Formula: CuSO4 · 5H2O
ⓘ Chalcophanite
Formula: ZnMn4+3O7 · 3H2O
ⓘ Coronadite
Formula: Pb(Mn4+6Mn3+2)O16
ⓘ Cryptomelane
Formula: K(Mn4+7Mn3+)O16
ⓘ Galena
Formula: PbS
ⓘ Goethite
Formula: Fe3+O(OH)
ⓘ Hematite
Formula: Fe2O3
ⓘ Hetaerolite
Formula: ZnMn2O4
ⓘ Lepidocrocite
Formula: Fe3+O(OH)
ⓘ 'Limonite'
References:
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Natrojarosite
Formula: NaFe3(SO4)2(OH)6
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrolusite
Formula: Mn4+O2
ⓘ Quartz
Formula: SiO2
ⓘ Ranciéite
Formula: (Ca,Mn2+)0.2(Mn4+,Mn3+)O2 · 0.6H2O
ⓘ Sphalerite
Formula: ZnS

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘSphalerite2.CB.05aZnS
ⓘGalena2.CD.10PbS
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘGoethite4.00.Fe3+O(OH)
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘHetaerolite4.BB.10ZnMn2O4
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
ⓘPyrolusite4.DB.05Mn4+O2
ⓘCoronadite4.DK.05aPb(Mn4+6Mn3+2)O16
ⓘCryptomelane4.DK.05aK(Mn4+7Mn3+)O16
ⓘLepidocrocite4.FE.15Fe3+O(OH)
ⓘChalcophanite4.FL.20ZnMn4+3O7 · 3H2O
ⓘRanciéite4.FL.40(Ca,Mn2+)0.2(Mn4+,Mn3+)O2 · 0.6H2O
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘAragonite5.AB.15CaCO3
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘBaryte7.AD.35BaSO4
ⓘNatrojarosite7.BC.10NaFe3(SO4)2(OH)6
ⓘChalcanthite7.CB.20CuSO4 · 5H2O
Group 8 - Phosphates, Arsenates and Vanadates
ⓘBeudantite8.BL.05PbFe3+3(AsO4)(SO4)(OH)6
Unclassified
ⓘ'Limonite'-

List of minerals for each chemical element

HHydrogen
Hⓘ BeudantitePbFe33+(AsO4)(SO4)(OH)6
Hⓘ ChalcophaniteZnMn34+O7 · 3H2O
Hⓘ ChalcanthiteCuSO4 · 5H2O
Hⓘ GoethiteFe3+O(OH)
Hⓘ LepidocrociteFe3+O(OH)
Hⓘ NatrojarositeNaFe3(SO4)2(OH)6
Hⓘ Ranciéite(Ca,Mn2+)0.2(Mn4+,Mn3+)O2 · 0.6H2O
CCarbon
Cⓘ AragoniteCaCO3
Cⓘ CalciteCaCO3
OOxygen
Oⓘ AragoniteCaCO3
Oⓘ BaryteBaSO4
Oⓘ BeudantitePbFe33+(AsO4)(SO4)(OH)6
Oⓘ CalciteCaCO3
Oⓘ ChalcophaniteZnMn34+O7 · 3H2O
Oⓘ ChalcanthiteCuSO4 · 5H2O
Oⓘ CoronaditePb(Mn64+Mn23+)O16
Oⓘ CryptomelaneK(Mn74+Mn3+)O16
Oⓘ GoethiteFe3+O(OH)
Oⓘ HematiteFe2O3
Oⓘ HetaeroliteZnMn2O4
Oⓘ LepidocrociteFe3+O(OH)
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ NatrojarositeNaFe3(SO4)2(OH)6
Oⓘ PyrolusiteMn4+O2
Oⓘ QuartzSiO2
Oⓘ Ranciéite(Ca,Mn2+)0.2(Mn4+,Mn3+)O2 · 0.6H2O
NaSodium
Naⓘ NatrojarositeNaFe3(SO4)2(OH)6
SiSilicon
Siⓘ QuartzSiO2
SSulfur
Sⓘ BaryteBaSO4
Sⓘ BeudantitePbFe33+(AsO4)(SO4)(OH)6
Sⓘ ChalcanthiteCuSO4 · 5H2O
Sⓘ GalenaPbS
Sⓘ NatrojarositeNaFe3(SO4)2(OH)6
Sⓘ PyriteFeS2
Sⓘ SphaleriteZnS
KPotassium
Kⓘ CryptomelaneK(Mn74+Mn3+)O16
CaCalcium
Caⓘ AragoniteCaCO3
Caⓘ CalciteCaCO3
Caⓘ Ranciéite(Ca,Mn2+)0.2(Mn4+,Mn3+)O2 · 0.6H2O
MnManganese
Mnⓘ ChalcophaniteZnMn34+O7 · 3H2O
Mnⓘ CoronaditePb(Mn64+Mn23+)O16
Mnⓘ CryptomelaneK(Mn74+Mn3+)O16
Mnⓘ HetaeroliteZnMn2O4
Mnⓘ PyrolusiteMn4+O2
Mnⓘ Ranciéite(Ca,Mn2+)0.2(Mn4+,Mn3+)O2 · 0.6H2O
FeIron
Feⓘ BeudantitePbFe33+(AsO4)(SO4)(OH)6
Feⓘ GoethiteFe3+O(OH)
Feⓘ HematiteFe2O3
Feⓘ LepidocrociteFe3+O(OH)
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ NatrojarositeNaFe3(SO4)2(OH)6
Feⓘ PyriteFeS2
CuCopper
Cuⓘ ChalcanthiteCuSO4 · 5H2O
ZnZinc
Znⓘ ChalcophaniteZnMn34+O7 · 3H2O
Znⓘ HetaeroliteZnMn2O4
Znⓘ SphaleriteZnS
AsArsenic
Asⓘ BeudantitePbFe33+(AsO4)(SO4)(OH)6
BaBarium
Baⓘ BaryteBaSO4
PbLead
Pbⓘ BeudantitePbFe33+(AsO4)(SO4)(OH)6
Pbⓘ CoronaditePb(Mn64+Mn23+)O16
Pbⓘ GalenaPbS

Other Regions, Features and Areas containing this locality

Eurasian PlateTectonic Plate
EuropeContinent

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