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Crotch Island, Stonington, Hancock County, Maine, USAi
Regional Level Types
Crotch IslandIsland
StoningtonTown
Hancock CountyCounty
MaineState
USACountry

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Type:
Mindat Locality ID:
219859
Long-form identifier:
mindat:1:2:219859:3
GUID (UUID V4):
0


Crotch Island is located in the Gulf of Maine just south of Stonington. The island is known for its granite quarries, which contain an attractive architectural texture known as rapakivi, where the alkali feldspar microcline is mantled by the plagioclase feldspar oligoclase or sometimes albite. "Rapakivi" is a Finnish word meaning "rotten." The original namesake rock in Finland was deeply weathered and was unsuitable for architectural needs. Legend holds that during a time when political tensions between Finland and Russia were high, Finnish officials had a statue of Czar Nicholas carved from rapakivi granite and shipped it to Moscow. The gesture was regarded as a "peace feeler" and the statue was emplaced in a prominent place in Moscow. After one winter's exposure, the statue began to crumble, and the gesture was seen as having a different purpose, and war nearly erupted as a result. The Maine rapakivi granite is unweathered and would have ensured that peace would prevail.

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Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded from this region.


Mineral List

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

11 valid minerals.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

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

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Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ Albite var. Oligoclase
Formula: (Na,Ca)[Al(Si,Al)Si2O8]
ⓘ 'Allanite Group'
Formula: (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
ⓘ 'Amphibole Supergroup'
Formula: AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Calcite
Formula: CaCO3
ⓘ Fluorapatite
Formula: Ca5(PO4)3F
ⓘ Ilmenite
Formula: Fe2+TiO3
ⓘ Laumontite
Formula: CaAl2Si4O12 · 4H2O
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Microcline
Formula: K(AlSi3O8)
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Quartz
Formula: SiO2
ⓘ 'Stilbite Subgroup'
Formula: M6-7[Al8-9Si27-28O72] · nH2O
ⓘ Titanite
Formula: CaTi(SiO4)O
ⓘ Zircon
Formula: Zr(SiO4)

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘIlmenite4.CB.05Fe2+TiO3
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 8 - Phosphates, Arsenates and Vanadates
ⓘFluorapatite8.BN.05Ca5(PO4)3F
Group 9 - Silicates
ⓘZircon9.AD.30Zr(SiO4)
ⓘTitanite9.AG.15CaTi(SiO4)O
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘMicrocline9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
ⓘvar. Oligoclase9.FA.35(Na,Ca)[Al(Si,Al)Si2O8]
ⓘLaumontite9.GB.10CaAl2Si4O12 · 4H2O
Unclassified
ⓘ'Amphibole Supergroup'-AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Stilbite Subgroup'-M6-7[Al8-9Si27-28O72] · nH2O
ⓘ'Allanite Group'-(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)

List of minerals for each chemical element

HHydrogen
Hⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ LaumontiteCaAl2Si4O12 · 4H2O
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Hⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ CalciteCaCO3
Oⓘ FluorapatiteCa5(PO4)3F
Oⓘ IlmeniteFe2+TiO3
Oⓘ LaumontiteCaAl2Si4O12 · 4H2O
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MicroclineK(AlSi3O8)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Oⓘ QuartzSiO2
Oⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Oⓘ TitaniteCaTi(SiO4)O
Oⓘ ZirconZr(SiO4)
Oⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
FFluorine
Fⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fⓘ FluorapatiteCa5(PO4)3F
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
Naⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ LaumontiteCaAl2Si4O12 · 4H2O
Alⓘ MicroclineK(AlSi3O8)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Alⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ LaumontiteCaAl2Si4O12 · 4H2O
Siⓘ MicroclineK(AlSi3O8)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Siⓘ QuartzSiO2
Siⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Siⓘ TitaniteCaTi(SiO4)O
Siⓘ ZirconZr(SiO4)
Siⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
PPhosphorus
Pⓘ FluorapatiteCa5(PO4)3F
ClChlorine
Clⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
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
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ FluorapatiteCa5(PO4)3F
Caⓘ LaumontiteCaAl2Si4O12 · 4H2O
Caⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Caⓘ TitaniteCaTi(SiO4)O
TiTitanium
Tiⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ IlmeniteFe2+TiO3
Tiⓘ TitaniteCaTi(SiO4)O
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ IlmeniteFe2+TiO3
Feⓘ MagnetiteFe2+Fe23+O4
ZrZirconium
Zrⓘ ZirconZr(SiO4)

Fossils

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

Localities in this Region

Other Regions, Features and Areas that Intersect

North AmericaContinent
North America PlateTectonic Plate

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