Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Horseshoe Island Calc-Silicate locality, Winthrop, Kennebec County, Maine, USAi
Regional Level Types
Horseshoe Island Calc-Silicate localityDeposit
WinthropTown
Kennebec CountyCounty
MaineState
USACountry

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Type:
Deposit
Mindat Locality ID:
7330
Long-form identifier:
mindat:1:2:7330:4
GUID (UUID V4):
0
Other Languages:
View 1 more...
Cebuano:
Horseshoe Island, Kennebec County, Maine


Calc-silicate deposit in metamorphic rock. The island is in Lake Cobbosseecontee.

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Standard Detailed Gallery Strunz Chemical Elements

Mineral List


4 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:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ Calcite
Formula: CaCO3
ⓘ Quartz
Formula: SiO2
ⓘ Quartz var. Smoky Quartz
Formula: SiO2
ⓘ Sillimanite
Formula: Al2(SiO4)O

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘSillimanite9.AF.05Al2(SiO4)O
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ CalciteCaCO3
Oⓘ QuartzSiO2
Oⓘ SillimaniteAl2(SiO4)O
Oⓘ Quartz var. Smoky QuartzSiO2
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
AlAluminium
Alⓘ SillimaniteAl2(SiO4)O
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ QuartzSiO2
Siⓘ SillimaniteAl2(SiO4)O
Siⓘ Quartz var. Smoky QuartzSiO2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ CalciteCaCO3
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2

Fossils

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

Other Databases

Wikidata ID:Q49641518
GeoNames ID:4967513


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