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Islets, Kupreanof Island, Petersburg Borough, Alaska, USAi
Regional Level Types
IsletsGroup of Islets
Kupreanof IslandIsland
Petersburg BoroughBorough
AlaskaState
USACountry

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Latitude & Longitude (WGS84):
56° 40' 38'' North , 133° 44' 20'' West
Latitude & Longitude (decimal):
56.67722,-133.73889
GeoHash:
G#: c40fkty2d
GRN:
N38W55
Type:
Group of Islets
Köppen climate type:
Cfb : Temperate oceanic climate
Nearest Settlements:
PlacePopulationDistance
Kake570 (2017)35.5km
Mindat Locality ID:
195979
Long-form identifier:
mindat:1:2:195979:9
GUID (UUID V4):
0


Rhyolites on islets off the SW coast south of Rocky Pass.

GPS coordinates are for Rocky Pass islet.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


6 valid minerals.

Detailed Mineral List:

ⓘ 'Apophyllite Group'
Formula: AB4[Si8O22]X · 8H2O
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Calcite
Formula: CaCO3
ⓘ 'Chabazite'
ⓘ Epistilbite
Formula: CaAl2Si6O16 · 5H2O
ⓘ 'Heulandite Subgroup'
Formula: (Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
ⓘ Laumontite
Formula: CaAl2Si4O12 · 4H2O
ⓘ Mordenite
Formula: (Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
ⓘ Quartz
Formula: SiO2
ⓘ Stilbite-Na
Formula: Na9(Si27Al9)O72 · 28H2O

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘLaumontite9.GB.10CaAl2Si4O12 · 4H2O
ⓘMordenite9.GD.35(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
ⓘEpistilbite9.GD.45CaAl2Si6O16 · 5H2O
ⓘStilbite-Na9.GE.10Na9(Si27Al9)O72 · 28H2O
Unclassified
ⓘ'Apophyllite Group'-AB4[Si8O22]X · 8H2O
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Chabazite'-
ⓘ'Heulandite Subgroup'-(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O

List of minerals for each chemical element

HHydrogen
Hⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ EpistilbiteCaAl2Si6O16 · 5H2O
Hⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Hⓘ LaumontiteCaAl2Si4O12 · 4H2O
Hⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Hⓘ Stilbite-NaNa9(Si27Al9)O72 · 28H2O
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ CalciteCaCO3
Oⓘ EpistilbiteCaAl2Si6O16 · 5H2O
Oⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Oⓘ LaumontiteCaAl2Si4O12 · 4H2O
Oⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Oⓘ QuartzSiO2
Oⓘ Stilbite-NaNa9(Si27Al9)O72 · 28H2O
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
NaSodium
Naⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Naⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Naⓘ Stilbite-NaNa9(Si27Al9)O72 · 28H2O
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ EpistilbiteCaAl2Si6O16 · 5H2O
Alⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Alⓘ LaumontiteCaAl2Si4O12 · 4H2O
Alⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Alⓘ Stilbite-NaNa9(Si27Al9)O72 · 28H2O
SiSilicon
Siⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ EpistilbiteCaAl2Si6O16 · 5H2O
Siⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Siⓘ LaumontiteCaAl2Si4O12 · 4H2O
Siⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Siⓘ QuartzSiO2
Siⓘ Stilbite-NaNa9(Si27Al9)O72 · 28H2O
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Kⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ EpistilbiteCaAl2Si6O16 · 5H2O
Caⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Caⓘ LaumontiteCaAl2Si4O12 · 4H2O
Caⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2

Other Regions, Features and Areas containing this locality

North America PlateTectonic Plate

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References

rruff-2.geo.arizona.edu (n.d.) https://rruff-2.geo.arizona.edu/uploads/CM35_691.pdf
Di Renzo, Francesco, Gabelica, Zelimir (1997) Barrerite and other zeolites from Kuiu and Kupreanof Islands, Alaska. The Canadian Mineralogist, 35 (3) 691-698
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