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Frassine, Monterotondo Marittimo, Grosseto Province, Tuscany, Italyi
Regional Level Types
FrassineDeposit
Monterotondo MarittimoCommune
Grosseto ProvinceProvince
TuscanyRegion
ItalyCountry

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Latitude & Longitude (WGS84):
43° 6' 56'' North , 10° 45' 58'' East
Latitude & Longitude (decimal):
Type:
Nearest Settlements:
PlacePopulationDistance
Monterotondo Marittimo994 (2014)8.0km
Monteverdi Marittimo365 (2014)8.2km
Lustignano156 (2014)8.3km
Suvereto2,117 (2014)8.4km
Canneto182 (2014)9.6km
Mindat Locality ID:
69394
Long-form identifier:
mindat:1:2:69394:6
GUID (UUID V4):
0


Sb-Au deposit.

Epithermal mineralization (Carlin type ?), with "invisible gold" (10 micron grains), associated with hydrothermally alteration (argillitic acid and alunitic acid) of host rocks : "Calcare Cavernoso" (Falda Toscana) and Verrucano (Monticiano-Roccastrada unit).

The limestones are partially dissolved (cavernous), silicified and argillitized.

The fluids at the origin of the mineralization are meteoritic hydrothermal fluids, of low salinity and low pH, in convective regime caused by the heat flux from the Larderello geothermal area (intrusive granite pluton / 4 Ma age).
Silica has been leached from deeper rock formations.

Gold and chromium enrichment is due to ophiolitic complex influence.

Source: Dr. GIOVANNI MONTINI, "Mineralizzazioni epitermali a oro nell'area di Frassine (GR)", Unpublished Paper, Firenze University).

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


15 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:

Alunite
Formula: KAl3(SO4)2(OH)6
Baryte
Formula: BaSO4
Bismuthinite
Formula: Bi2S3
Calcite
Formula: CaCO3
Goethite
Formula: Fe3+O(OH)
Hematite
Formula: Fe2O3
Kaolinite
Formula: Al2(Si2O5)(OH)4
Lepidocrocite
Formula: Fe3+O(OH)
Montmorillonite
Formula: (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Muscovite var. Illite
Formula: K0.65Al2.0[Al0.65Si3.35O10](OH)2
Native Gold
Formula: Au
Pyrite
Formula: FeS2
Quartz
Formula: SiO2
Stibiconite
Formula: Sb3+Sb5+2O6(OH)
Stibnite
Formula: Sb2S3
'Tetrahedrite Subgroup'
Formula: Cu6(Cu4C2+2)Sb4S12S

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Native Gold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
Bismuthinite2.DB.05Bi2S3
Stibnite2.DB.05Sb2S3
Pyrite2.EB.05aFeS2
'Tetrahedrite Subgroup'2.GB.05Cu6(Cu4C2+2)Sb4S12S
Group 4 - Oxides and Hydroxides
Goethite4.00.Fe3+O(OH)
Hematite4.CB.05Fe2O3
Quartz4.DA.05SiO2
Stibiconite4.DH.20Sb3+Sb5+2O6(OH)
Lepidocrocite4.FE.15Fe3+O(OH)
Group 5 - Nitrates and Carbonates
Calcite5.AB.05CaCO3
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
Baryte7.AD.35BaSO4
Alunite7.BC.10KAl3(SO4)2(OH)6
Group 9 - Silicates
Muscovite
var. Illite
9.EC.15K0.65Al2.0[Al0.65Si3.35O10](OH)2
9.EC.15KAl2(AlSi3O10)(OH)2
Montmorillonite9.EC.40(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Kaolinite9.ED.05Al2(Si2O5)(OH)4

List of minerals for each chemical element

HHydrogen
H AluniteKAl3(SO4)2(OH)6
H GoethiteFe3+O(OH)
H Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
H KaoliniteAl2(Si2O5)(OH)4
H LepidocrociteFe3+O(OH)
H MuscoviteKAl2(AlSi3O10)(OH)2
H Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
H StibiconiteSb3+Sb25+O6(OH)
CCarbon
C CalciteCaCO3
OOxygen
O AluniteKAl3(SO4)2(OH)6
O BaryteBaSO4
O CalciteCaCO3
O GoethiteFe3+O(OH)
O HematiteFe2O3
O Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
O KaoliniteAl2(Si2O5)(OH)4
O LepidocrociteFe3+O(OH)
O MuscoviteKAl2(AlSi3O10)(OH)2
O Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
O QuartzSiO2
O StibiconiteSb3+Sb25+O6(OH)
NaSodium
Na Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
MgMagnesium
Mg Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
AlAluminium
Al AluniteKAl3(SO4)2(OH)6
Al Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Al KaoliniteAl2(Si2O5)(OH)4
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
SiSilicon
Si Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Si KaoliniteAl2(Si2O5)(OH)4
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Si QuartzSiO2
SSulfur
S AluniteKAl3(SO4)2(OH)6
S BaryteBaSO4
S BismuthiniteBi2S3
S PyriteFeS2
S StibniteSb2S3
S Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
KPotassium
K AluniteKAl3(SO4)2(OH)6
K Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
K MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Ca CalciteCaCO3
Ca Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
FeIron
Fe GoethiteFe3+O(OH)
Fe HematiteFe2O3
Fe LepidocrociteFe3+O(OH)
Fe PyriteFeS2
CuCopper
Cu Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
SbAntimony
Sb StibiconiteSb3+Sb25+O6(OH)
Sb StibniteSb2S3
Sb Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
BaBarium
Ba BaryteBaSO4
AuGold
Au Native GoldAu
BiBismuth
Bi BismuthiniteBi2S3

Other Regions, Features and Areas containing this locality

Eurasian PlateTectonic Plate
EuropeContinent

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