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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Penfield Quarry (Oak Leaf Quarry), Portland, Middlesex County, Connecticut, USAi
Regional Level Types
Penfield Quarry (Oak Leaf Quarry)Quarry
PortlandTown
Middlesex CountyCounty
ConnecticutState
USACountry

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PhotosMapsSearchMineralogy
07419100017272014929126.jpg
Ishikawaite

Penfield Quarry, Portland, Middlesex County, Connecticut, USA
06365120017272014902314.jpg
Ishikawaite, etc.

Penfield Quarry, Portland, Middlesex County, Connecticut, USA
09735240017272043874870.jpg
Microlite Group

Penfield Quarry, Portland, Middlesex County, Connecticut, USA
00068300017272043927848.jpg
Ishikawaite

Penfield Quarry, Portland, Middlesex County, Connecticut, USA
06425900017272043932934.jpg
Ishikawaite, etc.

Penfield Quarry, Portland, Middlesex County, Connecticut, USA
09735240017272043874870.jpg
Microlite Group

Penfield Quarry, Portland, Middlesex County, Connecticut, USA
07419100017272014929126.jpg
Ishikawaite

Penfield Quarry, Portland, Middlesex County, Connecticut, USA
06365120017272014902314.jpg
Ishikawaite, etc.

Penfield Quarry, Portland, Middlesex County, Connecticut, USA
Latitude & Longitude (WGS84):
41° 35' 47'' North , 72° 34' 32'' West
Latitude & Longitude (decimal):
41.59643,-72.57561
GRN:
N28W40
Type:
Quarry
Köppen climate type:
Dfa : Hot-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Lake Pocotopaug3,436 (2017)5.4km
Cromwell13,750 (2017)5.8km
Portland5,862 (2017)6.0km
East Hampton2,691 (2017)6.5km
Middletown46,756 (2017)7.3km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Lapidary and Mineral Society of Central ConnecticutMeriden, Connecticut20km
Bristol Gem & Mineral ClubBristol, Connecticut32km
New Haven Mineral ClubNew Haven, Connecticut43km
Mindat Locality ID:
18304
Long-form identifier:
mindat:1:2:18304:1
GUID (UUID V4):
0


An old feldspar quarry in a granite pegmatite.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


9 valid minerals.

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
References:
Eric Quinter collectionIdentified by Harold Moritz: Visual Identification
ⓘ Annite
Formula: KFe2+3(AlSi3O10)(OH)2
ⓘ Beryl
Formula: Be3Al2(Si6O18)
ⓘ Columbite-(Fe)
Formula: Fe2+Nb2O6
Habit: tabular
Colour: black with blue iridescence
✪ Ishikawaite
Formula: U4+Fe2+Nb2O8
Habit: tabular
Colour: black with brown coating
Description: metamict crystals with obsidian-like conchoidal fracture
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Microcline
Formula: K(AlSi3O8)
Colour: pale brown
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Quartz
Formula: SiO2
Colour: smoky

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz4.DA.05SiO2
ⓘIshikawaite4.DB.25U4+Fe2+Nb2O8
ⓘColumbite-(Fe)4.DB.35Fe2+Nb2O6
Group 9 - Silicates
ⓘBeryl9.CJ.05Be3Al2(Si6O18)
ⓘ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ⓘ MuscoviteKAl2(AlSi3O10)(OH)2
BeBeryllium
Beⓘ BerylBe3Al2(Si6O18)
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ AnniteKFe32+(AlSi3O10)(OH)2
Oⓘ BerylBe3Al2(Si6O18)
Oⓘ Columbite-(Fe)Fe2+Nb2O6
Oⓘ IshikawaiteU4+Fe2+Nb2O8
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MicroclineK(AlSi3O8)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ AnniteKFe32+(AlSi3O10)(OH)2
Alⓘ BerylBe3Al2(Si6O18)
Alⓘ MicroclineK(AlSi3O8)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ AnniteKFe32+(AlSi3O10)(OH)2
Siⓘ BerylBe3Al2(Si6O18)
Siⓘ MicroclineK(AlSi3O8)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
KPotassium
Kⓘ AnniteKFe32+(AlSi3O10)(OH)2
Kⓘ MicroclineK(AlSi3O8)
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
FeIron
Feⓘ AnniteKFe32+(AlSi3O10)(OH)2
Feⓘ Columbite-(Fe)Fe2+Nb2O6
Feⓘ IshikawaiteU4+Fe2+Nb2O8
Feⓘ MagnetiteFe2+Fe23+O4
NbNiobium
Nbⓘ Columbite-(Fe)Fe2+Nb2O6
Nbⓘ IshikawaiteU4+Fe2+Nb2O8
UUranium
Uⓘ IshikawaiteU4+Fe2+Nb2O8

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

Montague, S. A. (1937): Some Mineral Localities Near Portland, Conn. Rocks & Minerals: 12 (5): 145.
Hanson, S. L., Jarnot, B. M., Falster, A. U., Simmons, W. B., Nizamoff, J. W. (2003): Nb-Ta-Ti Oxide Minerals from Two Pegmatites of the Middletown Area, Connecticut, abstract in Contributed Papers in Specimen Mineralogy, Part 2, 30th Rochester Mineralogical Symposium. Rocks & Minerals: 79(4): 255.
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