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Guilford, New Haven County, Connecticut, USAi
Regional Level Types
GuilfordTown
New Haven CountyCounty
ConnecticutState
USACountry

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PhotosMapsSearch
08922520017272043229669.jpg
Sillimanite

Guilford, New Haven County, Connecticut, USA
02661390017369087622287.jpg
Rutile, etc.

Guilford, New Haven County, Connecticut, USA
03769970017589207442649.jpg
Cordierite, etc.

Hungry Hill, Guilford, New Haven County, Connecticut, USA
01686890017272080049053.jpg
Sillimanite

Guilford, New Haven County, Connecticut, USA
09915460017368176874572.jpg
Rutile, etc.

Guilford, New Haven County, Connecticut, USA
07866590017587480865870.jpg
Cordierite, etc.

Hungry Hill, Guilford, New Haven County, Connecticut, USA
08922520017272043229669.jpg
Sillimanite

Guilford, New Haven County, Connecticut, USA
02661390017369087622287.jpg
Rutile, etc.

Guilford, New Haven County, Connecticut, USA
Neighbouring regions:
Madison, New Haven County, Connecticut, USA
Durham, Middlesex County, Connecticut, USA
Branford, New Haven County, Connecticut, USA
Type:
Town
Largest Settlements:
PlacePopulation
Guilford22,498 (2017)
Guilford Center2,597 (2017)
Mindat Locality ID:
53544
Long-form identifier:
mindat:1:2:53544:8
GUID (UUID V4):
0
Other/historical names associated with this locality:
Menunkatuck


Guilford is a town.

Select Mineral List Type

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

12 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

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ Almandine
Formula: Fe2+3Al2(SiO4)3
Colour: red
Description: In the gneiss, but separate from the grossular-vesuvianite veins.
ⓘ 'Apatite'
Formula: Ca5(PO4)3(Cl/F/OH)
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
✪ Cordierite
Formula: Mg2Al4Si5O18
Habit: anhedral to stubby subhedral, prismatic
Colour: violet, smoky blue, deep blue to light blue; dichroic
Fluorescence: none
Description: In a biotite, quartz, and plagioclase gneiss. Crystals to several cm, best formed in quartz-rich zones. Some gems have been cut from this material - see gem display at the American Museum of Natural History in New York City.
ⓘ Fluorapatite
Formula: Ca5(PO4)3F
References:
Dana 6:767.
ⓘ Fluorite
Formula: CaF2
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ Grossular
Formula: Ca3Al2(SiO4)3
Habit: dodecahedral
Colour: orange-brown, yellowish red
Description: "The garnet also is massive, but it shows many crystalline points of clear material. Its color is yellowish red, and its appearance entirely different from that of the deep red individual garnets which are so common in the gneiss....The veins vary from half an inch to four inches in width coincide with the bedding of the gneiss, and are seen for only 100 feet on the east side of a ledge but fifty feet wide. No cordierite was found in this ledge. Many garnets of value as gems have been taken from the ledge in the last six years." Hovey, 1888.
ⓘ 'Hornblende Root Name Group'
Formula: ◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2
ⓘ 'Monazite Group'
Formula: REE(PO4)
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2
ⓘ Rutile
Formula: TiO2
Habit: prismatic
Colour: metallic exterior with red interior
Description: One specimen with crude, unterminated, elongated prismatic crystals to 22 mm with square cross-section in massive quartz.
ⓘ Sillimanite
Formula: Al2(SiO4)O
Habit: acicular
Colour: white
Description: As inclusions in the cordierite according to Hovey (1888).
ⓘ Vesuvianite
Formula: Ca19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
Habit: anhedral to subhedral prismatic
Colour: dark green
Description: Associated with the yellowish red garnet in hornblende schist and gneiss

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘPyrite2.EB.05aFeS2
Group 3 - Halides
ⓘFluorite3.AB.25CaF2
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
ⓘRutile4.DB.05TiO2
Group 8 - Phosphates, Arsenates and Vanadates
ⓘFluorapatite8.BN.05Ca5(PO4)3F
Group 9 - Silicates
ⓘAlmandine9.AD.25Fe2+3Al2(SiO4)3
ⓘGrossular9.AD.25Ca3Al2(SiO4)3
ⓘSillimanite9.AF.05Al2(SiO4)O
ⓘVesuvianite9.BG.35Ca19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
ⓘCordierite9.CJ.10Mg2Al4Si5O18
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘAlbite9.FA.35Na(AlSi3O8)
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Monazite Group'-REE(PO4)
ⓘ'Hornblende Root Name Group'-◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2
ⓘ'Garnet Group'-X3Z2(SiO4)3
ⓘ'Apatite'-Ca5(PO4)3(Cl/F/OH)

List of minerals for each chemical element

HHydrogen
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
Hⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Hⓘ ApatiteCa5(PO4)3(Cl/F/OH)
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ AlmandineFe32+Al2(SiO4)3
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ CordieriteMg2Al4Si5O18
Oⓘ FluorapatiteCa5(PO4)3F
Oⓘ GrossularCa3Al2(SiO4)3
Oⓘ Monazite GroupREE(PO4)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ RutileTiO2
Oⓘ SillimaniteAl2(SiO4)O
Oⓘ VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
Oⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Oⓘ Garnet GroupX3Z2(SiO4)3
Oⓘ ApatiteCa5(PO4)3(Cl/F/OH)
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fⓘ FluorapatiteCa5(PO4)3F
Fⓘ FluoriteCaF2
Fⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Fⓘ ApatiteCa5(PO4)3(Cl/F/OH)
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ CordieriteMg2Al4Si5O18
Mgⓘ VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ AlmandineFe32+Al2(SiO4)3
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ CordieriteMg2Al4Si5O18
Alⓘ GrossularCa3Al2(SiO4)3
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ SillimaniteAl2(SiO4)O
Alⓘ VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
Alⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ AlmandineFe32+Al2(SiO4)3
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ CordieriteMg2Al4Si5O18
Siⓘ GrossularCa3Al2(SiO4)3
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ SillimaniteAl2(SiO4)O
Siⓘ VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
Siⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Siⓘ Garnet GroupX3Z2(SiO4)3
PPhosphorus
Pⓘ FluorapatiteCa5(PO4)3F
Pⓘ Monazite GroupREE(PO4)
Pⓘ ApatiteCa5(PO4)3(Cl/F/OH)
SSulfur
Sⓘ PyriteFeS2
ClChlorine
Clⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Clⓘ ApatiteCa5(PO4)3(Cl/F/OH)
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ FluorapatiteCa5(PO4)3F
Caⓘ FluoriteCaF2
Caⓘ GrossularCa3Al2(SiO4)3
Caⓘ VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9
Caⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Caⓘ ApatiteCa5(PO4)3(Cl/F/OH)
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ RutileTiO2
FeIron
Feⓘ AlmandineFe32+Al2(SiO4)3
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ PyriteFeS2
Feⓘ VesuvianiteCa19Fe3+Al4(Al6Mg2)(◻4)◻[Si2O7]4[(SiO4)10]O(OH)9

Fossils

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

Other Databases

Wikipedia:https://en.wikipedia.org/wiki/Guilford,_Connecticut
Wikidata ID:Q753857
GeoNames ID:4835531

Localities in this Region

USA

Other Regions, Features and Areas that Intersect

North AmericaContinent
North America PlateTectonic Plate

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