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Ronco tunnel (Bedretto window; Ronco window) [north section], Oberwald, Obergoms, Goms, Valais, Switzerlandi
Regional Level Types
Ronco tunnel (Bedretto window; Ronco window) [north section]Tunnel
OberwaldMunicipality (Former)
ObergomsMunicipality
GomsDistrict
ValaisCanton
SwitzerlandCountry

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Type:
Tunnel
Mindat Locality ID:
342754
Long-form identifier:
mindat:1:2:342754:8
GUID (UUID V4):
0
Other Languages:
German:
Ronco-Stollen (Bedrettofenster; Roncofenster) [Nordteil], Obergoms, Bezirk Goms, Wallis, Schweiz
Italian:
Galleria di Ronco (Finestra di Bedretto; Finestra di Ronco) [sezione nord], Obergoms, Distretto di Goms, Vallese, Svizzera


North section of the access tunnel to the Furka base tunnel.
The Bedretto tunnel was built in the 1970s as an auxiliary access drift to the Furka base tunnel. After completion of the Furka base tunnel, it was completely abandoned. The portal of the 5.22-km-long Bedretto tunnel is located close to the village of Ronco (Bedretto, Ticino), southeast of Pizzo Rotondo.

The tunnel penetrates the Variscan Rotondo granite, which intruded the Palaeozoic polymetamorphic crystalline basement rocks of the Gotthard massif
at 294.3 ± 1.1 Ma. The major mineral components of the Rotondo granite are albite, K feldspar, quartz, muscovite and biotite. Epidote-clinozoisite, chlorite, zircon, titanite, and carbonates are present as accessory minerals. Amongst opaque ore minerals pyrite is most abundant.


Note: for the south section (Bedretto, Leventina, Ticino), see https://www.mindat.org/loc-133274.html

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


13 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:

ⓘ Albite
Formula: Na(AlSi3O8)
Description: A large cleft rich in hematite and albite crystals was found in Rotondo granite, at ca. 3420 m from the portal.
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Calcite
Formula: CaCO3
ⓘ Clinochlore
Formula: Mg5Al(AlSi3O10)(OH)8
ⓘ 'Clinozoisite-Epidote Series'
ⓘ Hematite
Formula: Fe2O3
Description: A large cleft rich in hematite and albite crystals was found in Rotondo granite, at ca. 3420 m from the portal.
ⓘ 'K Feldspar'
ⓘ Laumontite
Formula: CaAl2Si4O12 · 4H2O
ⓘ Montmorillonite
Formula: (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Parauranophane
Formula: Ca(UO2)2(SiO3OH)2 · 5H2O
Description: As thin yellow crusts in Rotondo granite, at ca. 4181-4195 m from the portal.
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2
ⓘ Sepiolite
Formula: Mg4(Si6O15)(OH)2 · 6H2O
Description: In Rotondo granite, at ca. 5221 m from the portal.
ⓘ 'Stilbite Subgroup'
Formula: M6-7[Al8-9Si27-28O72] · nH2O
Description: In Rotondo granite, at ca. 4181-4195 m from the portal.
ⓘ Titanite
Formula: CaTi(SiO4)O
ⓘ Zircon
Formula: Zr(SiO4)

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘZircon9.AD.30Zr(SiO4)
ⓘTitanite9.AG.15CaTi(SiO4)O
ⓘParauranophane9.AK.15Ca(UO2)2(SiO3OH)2 · 5H2O
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘMontmorillonite9.EC.40(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
ⓘClinochlore9.EC.55Mg5Al(AlSi3O10)(OH)8
ⓘSepiolite9.EE.25Mg4(Si6O15)(OH)2 · 6H2O
ⓘAlbite9.FA.35Na(AlSi3O8)
ⓘLaumontite9.GB.10CaAl2Si4O12 · 4H2O
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Stilbite Subgroup'-M6-7[Al8-9Si27-28O72] · nH2O
ⓘ'Clinozoisite-Epidote Series'-
ⓘ'K Feldspar'-

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ⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Hⓘ LaumontiteCaAl2Si4O12 · 4H2O
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Hⓘ SepioliteMg4(Si6O15)(OH)2 · 6H2O
Hⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Hⓘ ParauranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Hⓘ Clinozoisite-Epidote Series
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ CalciteCaCO3
Oⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Oⓘ HematiteFe2O3
Oⓘ LaumontiteCaAl2Si4O12 · 4H2O
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Oⓘ QuartzSiO2
Oⓘ SepioliteMg4(Si6O15)(OH)2 · 6H2O
Oⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Oⓘ TitaniteCaTi(SiO4)O
Oⓘ ParauranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Oⓘ ZirconZr(SiO4)
Oⓘ Clinozoisite-Epidote Series
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
Naⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Mgⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Mgⓘ SepioliteMg4(Si6O15)(OH)2 · 6H2O
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Alⓘ LaumontiteCaAl2Si4O12 · 4H2O
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Alⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Alⓘ Clinozoisite-Epidote Series
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Siⓘ LaumontiteCaAl2Si4O12 · 4H2O
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Siⓘ QuartzSiO2
Siⓘ SepioliteMg4(Si6O15)(OH)2 · 6H2O
Siⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Siⓘ TitaniteCaTi(SiO4)O
Siⓘ ParauranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Siⓘ ZirconZr(SiO4)
Siⓘ Clinozoisite-Epidote Series
SSulfur
Sⓘ PyriteFeS2
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ LaumontiteCaAl2Si4O12 · 4H2O
Caⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Caⓘ TitaniteCaTi(SiO4)O
Caⓘ ParauranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Caⓘ Clinozoisite-Epidote Series
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ TitaniteCaTi(SiO4)O
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ HematiteFe2O3
Feⓘ PyriteFeS2
Feⓘ Clinozoisite-Epidote Series
ZrZirconium
Zrⓘ ZirconZr(SiO4)
UUranium
Uⓘ ParauranophaneCa(UO2)2(SiO3OH)2 · 5H2O

Fossils

This region is too big or complex to display the fossil list, try looking at smaller subregions.
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

Kipfer, A., and Stuker, P.(1979) Mineralien an dem Rotondogranit, TI. Schweizer Strahler, 5, 45-91
Stalder, H.A., Wagner, A., Graeser, S., Stuker, P. (1998) Mineralienlexikon der Schweiz. Wepf.
Lützenkirchen, V., and Loew, S. (2011) Late Alpine brittle faulting in the Rotondo granite (Switzerland): deformation mechanisms and fault evolution. Swiss Journal of Geosciences, 104, 31–54.
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