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Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USAi
Regional Level Types
Forest Ridge RoadRoad
HigganumVillage
HaddamTown
Middlesex CountyCounty
ConnecticutState
USACountry

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PhotosMapsSearch
04139820017490454108629.jpg
Road Cut, Image 1

Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USA
07842740017490454104235.jpg
Road Cut, Image 02

Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USA
06416870017272020978058.jpg
Opal-AN

Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USA
08731950017416650639413.jpg
Road Cut, Image 1

Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USA
05489040017416622882960.jpg
Road Cut, Image 02

Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USA
06416870017272020978058.jpg
Opal-AN

Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USA
04139820017490454108629.jpg
Road Cut, Image 1

Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USA
07842740017490454104235.jpg
Road Cut, Image 02

Forest Ridge Road, Higganum, Haddam, Middlesex County, Connecticut, USA
Latitude & Longitude (WGS84):
41° 29' 28'' North , 72° 32' 28'' West
Latitude & Longitude (decimal):
41.49111,-72.54111
GRN:
N28W40
Type:
Road
Köppen climate type:
Cfa : Humid subtropical climate
Mindat Locality ID:
264352
Long-form identifier:
mindat:1:2:264352:9
GUID (UUID V4):
0


Road cuts for residential development exposed small common pegmatites and the host rock Ordovician Pond Meadow Gneiss. Besides the rock-forming pegmatite minerals are highly fluorescent coatings of opal-AN.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


9 valid minerals.

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
Habit: anhedral
Colour: white
ⓘ Almandine
Formula: Fe2+3Al2(SiO4)3
Habit: trapezohedral to anhedral grains
Colour: maroon
Description: tiny accessory grains
ⓘ Annite
Formula: KFe2+3(AlSi3O10)(OH)2
Description: tiny accessory flakes
ⓘ Hematite
Formula: Fe2O3
Habit: stains
Description: stains probably from the oxidation of magnetite
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
Habit: striated octahedrons
Colour: metallic gray-black
Description: mostly small accessory grains
ⓘ Microcline
Formula: K(AlSi3O8)
Habit: anhedral
Colour: pink
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Description: micaceous accessory in small grains
✪ Opal
Formula: SiO2 · nH2O
Habit: encrustations
Colour: colorless
Fluorescence: bright green
Description: Gelatinous coatings and encrustations, some easily visible without using a UV lamp, on both pegmatite and host gneiss. UV response best in SW, progressively less in MW to LW.
✪ Opal var. Opal-AN
Formula: SiO2 · nH2O
Habit: encrustations
Colour: colorless
Fluorescence: bright green
Description: Gelatinous coatings and encrustations, some easily visible without using a UV lamp, on both pegmatite and host gneiss. UV response best in SW, progressively less in MW to LW.
ⓘ Quartz
Formula: SiO2
Habit: masive
Colour: black
ⓘ Quartz var. Smoky Quartz
Formula: SiO2
Habit: masive
Colour: black

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
ⓘOpal
var. Opal-AN		4.DA.10SiO2 · nH2O
ⓘ4.DA.10SiO2 · nH2O
Group 9 - Silicates
ⓘAlmandine9.AD.25Fe2+3Al2(SiO4)3
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘAnnite9.EC.20KFe2+3(AlSi3O10)(OH)2
ⓘMicrocline9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)

List of minerals for each chemical element

HHydrogen
Hⓘ AnniteKFe32+(AlSi3O10)(OH)2
Hⓘ Opal var. Opal-ANSiO2 · nH2O
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ OpalSiO2 · nH2O
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ AnniteKFe32+(AlSi3O10)(OH)2
Oⓘ AlmandineFe32+Al2(SiO4)3
Oⓘ HematiteFe2O3
Oⓘ Opal var. Opal-ANSiO2 · nH2O
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MicroclineK(AlSi3O8)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ OpalSiO2 · nH2O
Oⓘ QuartzSiO2
Oⓘ Quartz var. Smoky QuartzSiO2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ AnniteKFe32+(AlSi3O10)(OH)2
Alⓘ AlmandineFe32+Al2(SiO4)3
Alⓘ MicroclineK(AlSi3O8)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ AnniteKFe32+(AlSi3O10)(OH)2
Siⓘ AlmandineFe32+Al2(SiO4)3
Siⓘ Opal var. Opal-ANSiO2 · nH2O
Siⓘ MicroclineK(AlSi3O8)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ OpalSiO2 · nH2O
Siⓘ QuartzSiO2
Siⓘ Quartz var. Smoky QuartzSiO2
KPotassium
Kⓘ AnniteKFe32+(AlSi3O10)(OH)2
Kⓘ MicroclineK(AlSi3O8)
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
FeIron
Feⓘ AnniteKFe32+(AlSi3O10)(OH)2
Feⓘ AlmandineFe32+Al2(SiO4)3
Feⓘ HematiteFe2O3
Feⓘ MagnetiteFe2+Fe23+O4

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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

Former Don Miller collection
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