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Nathan Hall Quarry, East Hampton, Middlesex County, Connecticut, USAi
Regional Level Types
Nathan Hall QuarryQuarry
East HamptonTown
Middlesex CountyCounty
ConnecticutState
USACountry

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Latitude & Longitude (WGS84):
41° 35' 38'' North , 72° 32' 24'' West
Latitude & Longitude (decimal):
Type:
Nearest Settlements:
PlacePopulationDistance
Lake Pocotopaug3,436 (2017)2.5km
East Hampton2,691 (2017)3.7km
Terramuggus1,025 (2017)7.4km
Portland5,862 (2017)8.7km
Cromwell13,750 (2017)8.8km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Lapidary and Mineral Society of Central ConnecticutMeriden, Connecticut23km
Bristol Gem & Mineral ClubBristol, Connecticut35km
New Haven Mineral ClubNew Haven, Connecticut45km
Mindat Locality ID:
29586
Long-form identifier:
mindat:1:2:29586:9
GUID (UUID V4):
0
Other/historical names associated with this locality:
Clark Hill Quarry


The Nathan Hall Quarry (one of the quarries on Clark Hill) is located in the Meshomasic State Forest off of Woodchopper's Road. It is a small quarry in a zoned granite pegmatite and based on the few references, it appears to have operated completely before 1922. There is nothing specific in the mineralogical literature, but presumably it was quarried for feldspar and/or mica. The F. W. Beers County Atlas of Middlesex, Connecticut, published in 1874, shows a large rectangle of land north of Clark Hill Road owned by "N. Hall". The Hall Cemetery is on Clark Hill Road near the entrance to Woodchopper's Road. It is often incorrectly called the Nathan Hale Quarry (such as Schooner, circa 1980s) and is sometimes confused with the State Forest Quarry #1 just to the north.

Note: Collecting is allowed only via permit issued by the Connecticut DEEP to educational organizations (schools, mineral clubs, etc.). See https://portal.ct.gov/deep/geology/mineral-collecting

Besides the rock-forming albite, microcline and quartz, sharp muscovite crystals are very common and the large, dark almandine garnets, although fairly rare, are noteworthy. XRF analyses of several garnets from Nathan Hall show them all to be almandine (>0.50 Fe/(Fe+Mn), but with a significant (0.23 to 0.47) spessartine component. As a result, black Mn oxy/hydroxide stains typical cover and surround these crystals but is not a reliable indicator of species. Annite (formerly known as "biotite") is also common, mostly in bladed crystals up to several feet long. Beryl is uncommon, but crystals can be large, gemmy, and terminated and vary in color from yellow through green to aqua. Zircon, uranium minerals (beautiful meta-autunite and metatorbernite halos around uranophane-altered uraninite), and fluorapatite are sprinkled throughout. There is schorl, plus interesting tapered to knobby pseudomorphs of muscovite after schorl. Schorl also occurs in the adjacent Littleton schist. Massive quartz, which encloses the sharp micas and matrix microclines, is very abundant at Hall, but good crystals are usually pocket micros. Although tiny columbite-(Fe) crystals are common, large ones are very rare but well-formed. Rare finds of loellingite, tantalite-(Fe), monazite-(Ce) and tapiolite-(Fe) crystals were confirmed by various analytical methods.

One mystery about this locality is the reported abundance of rose quartz by Foye (1922). Very little if any true rose quartz has been found here despite myriad field trips since the early 1990s (it is present at the nearby State Forest Quarry #1, which did not open until the early 1940s). One possible resolution is that the rose quartz is really from the small quarry in Cobalt along Great Hill Pond Brook that Hiller's 1971 collecting guide book calls the "Nathan Hale Quarry". The names Nathan Hale (the famous official State Hero) and Nathan Hall are commonly confused and Nathan Hall had several quarries, with the one in Cobalt thus possibly one if his also. This small quarry was described by Rice and Foye in their 1927 guide to Middletown area geology, though not given a name, nor did they mention rose quartz. However, Foye worked at Wesleyan University in Middletown and on display there at the Joe Webb Peoples Museum is a large specimen of rose quartz with the locality given as "Cobalt". It seems likely he may have confused the origin of the rose quartz (though the location of the Nathan Hall Quarry is correct in Foye (1922)), especially if Nathan Hall operated both quarries. Unfortunately, the quarry on Great Hill Pond Brook has been inaccessible for several decades.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


25 valid minerals. 2 erroneous literature entries.

Detailed Mineral List:

Albite
Formula: Na(AlSi3O8)
Colour: white
Description: Euhedral crystals restricted to the lining of small pockets.
Almandine
Formula: Fe2+3Al2(SiO4)3
Habit: complex mix of forms, generally modified trapezohedrons
Colour: maroon
Description: 7 specimens were tested for Fe and Mn content using X-ray fluorescence. The Mn percentage of the total Fe+Mn content varied from 23 to 47%, indicating there were all almandine. Crystals are typically coated with dark, probable Mn oxides coating, but this does not prove they are spessartine.
Annite
Formula: KFe2+3(AlSi3O10)(OH)2
Habit: elongated tabular subhedral
Colour: black
Description: Crystals apparently reached several dm long as they are typically found as fragments in the dump, sometimes interlayered with muscovite.
Autunite
Formula: Ca(UO2)2(PO4)2 · 10-12H2O
Beryl
Formula: Be3Al2(Si6O18)
Habit: elongated prisms with pinacoidal or somewhat rounded pyramidal terminations
Colour: yellow, pale green, aqua
Description: Crystals found frozen in fragments of the intermediate zone (quartz, albite, some muscovite) of the pegmatite.
Bismutite
Formula: (BiO)2CO3
Columbite-(Fe)
Formula: Fe2+Nb2O6
Habit: skeletal, tabular, stout or elongated prisms
Colour: black with iridescence
Description: Wide variety of crystal habits, stout prisms reach a about 3 x 5 cm, while skeletal crystals intergrown with albite can reach 8 cm. Several crystals tested using XRD and Raman spectroscopy.
Fluorapatite
Formula: Ca5(PO4)3F
Habit: anhedral to subhedral grains
Colour: pale gray-green
Fluorescence: yellow
Description: subhedral grains can reach several cm
Foitite
Formula: ◻(Fe2+2Al)Al6(Si6O18)(BO3)3(OH)3(OH)
Habit: massive material, skeletal/interstitial in graphic granite
Colour: black
Description: Tested by Raman spectroscopy at the University of New Haven, spectrum was weak but consistent with foitite. Thin masses interstitial within microcline/quartz graphic granite, unusual as that association is typically barren of interesting minerals. Follow up: 2021 EDS analysis by Al Falster at Maine Mineral & Gem Museum indicates a member of the elbaite - schorl series.
Goethite
Formula: Fe3+O(OH)
Löllingite
Formula: FeAs2
Meta-autunite
Formula: Ca(UO2)2(PO4)2 · 6H2O
Habit: encrustations
Colour: yellow
Fluorescence: green
Description: excellent halos surrounding other uranium secondary minerals and altered uraninite.
Metatorbernite
Formula: Cu(UO2)2(PO4)2 · 8H2O
Habit: square tabular
Colour: green
Description: usually anhedral crusts and associated with other secondary U minerals
Microcline
Formula: K(AlSi3O8)
Habit: prismatic
Colour: tan
Description: rare in good crystals, some fragments found
Monazite-(Ce)
Formula: Ce(PO4)
Habit: tabular subhedral
Colour: brown
Description: One small glassy subhedral crystal found and confirmed by X-ray diffraction test.
Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Habit: tabular, pseudo-hexagonal
Colour: silver
Description: Anhedral in the intermediate zone, but euhedral along the contact of this zone with the quartz core. Also as fine-grained pseudomorphs after euhedral schorl.
Opal
Formula: SiO2 · nH2O
Habit: encrustations
Colour: colorless
Fluorescence: green
Description: inconspicuous unless illuminated by SW UV.
Opal var. Opal-AN
Formula: SiO2 · nH2O
Habit: encrustations
Colour: colorless
Fluorescence: green
Description: inconspicuous unless illuminated by SW UV.
Quartz
Formula: SiO2
Colour: clear, white
Quartz var. Ferruginous Quartz
Formula: SiO2
Quartz var. Rose Quartz
Formula: SiO2
Colour: pink
Description: Although reported by Foye (1922), no modern specimens found. Perhaps he was referring to the abundant ferruginous quartz.
Quartz var. Smoky Quartz
Formula: SiO2
Colour: grey to black
Schorl
Formula: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
Habit: elongated prisms with shallow rhombohedral terminations
Colour: black
Description: generally anhedral to subhedral, crystals crumble readily. Euhedral crystals pseudomorphed by fine-grained muscovite are common.
Spessartine
Formula: Mn2+3Al2(SiO4)3
Description: As a component in almandine, not verified as a separate species. XRF testing of 7 garnets found Mn/(Fe+Mn) ranged from 0.23 to 0.47. Black Mn oxy/hydroxide staining associated with garnets is not a reliable indicator of spessartine as many garnets from here show such staining but have tested as almandine.
Staurolite
Formula: Fe2+2Al9Si4O23(OH)
References:
Tantalite-(Fe)
Formula: Fe2+Ta2O6
Habit: rectangular prismatic
Colour: black with bluish iridescence
Description: One columbite-tantalite crystal (https://www.mindat.org/photo-275489.html) suspected from its high SG of being tantalite was analyzed by SEM-EDS and found to be tantalite-(Fe). There may be more as each crystal would need to be tested to confirm and few have been.
Tapiolite-(Fe)
Formula: Fe2+Ta2O6
Habit: Complex, twinned short prisms or pyramidal tetragonal.
Colour: black
Description: Three specimens are known, with very similar with crystals about 3-4 cm, in quartz, albite and/or muscovite. Two are complexly crystallized apparently twinned, that somewhat resemble garnets, but of course black and submetallic. Other than one specimen from the Hale Quarry, this is the only known Connecticut location for this mineral. An additional three specimens were collected in the 1980's by David Busha but remained unidentified until 2019.
Torbernite
Formula: Cu(UO2)2(PO4)2 · 12H2O
Uraninite
Formula: UO2
Habit: octahedral
Colour: black
Description: Typically highly altered and surrounded by secondary U mineral haloes.
Uranophane
Formula: Ca(UO2)2(SiO3OH)2 · 5H2O
Colour: yellow
Description: Usually replacing small uraninite crystals.
'Yttrocolumbite-(Y)' ?
Formula: Y(U4+,Fe2+)Nb2O8
Description: Extremely rare mineral. No chemical data available.
Zircon
Formula: Zr(SiO4)
Habit: radiating aggregates
Colour: brown
Description: Usually small, inconspicuous brown radiating aggregates, often stained with limonite.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
Löllingite2.EB.15aFeAs2
Group 4 - Oxides and Hydroxides
Goethite4.00.Fe3+O(OH)
Quartz4.DA.05SiO2
var. Rose Quartz4.DA.05SiO2
var. Smoky Quartz4.DA.05SiO2
var. Ferruginous Quartz4.DA.05SiO2
Opal
var. Opal-AN
4.DA.10SiO2 · nH2O
4.DA.10SiO2 · nH2O
Tapiolite-(Fe)4.DB.10Fe2+Ta2O6
'Yttrocolumbite-(Y)' ?4.DB.25Y(U4+,Fe2+)Nb2O8
Columbite-(Fe)4.DB.35Fe2+Nb2O6
Tantalite-(Fe)4.DB.35Fe2+Ta2O6
Uraninite4.DL.05UO2
Group 5 - Nitrates and Carbonates
Bismutite5.BE.25(BiO)2CO3
Group 8 - Phosphates, Arsenates and Vanadates
Monazite-(Ce)8.AD.50Ce(PO4)
Fluorapatite8.BN.05Ca5(PO4)3F
Autunite8.EB.05Ca(UO2)2(PO4)2 · 10-12H2O
Torbernite8.EB.05Cu(UO2)2(PO4)2 · 12H2O
Meta-autunite8.EB.10Ca(UO2)2(PO4)2 · 6H2O
Metatorbernite8.EB.10Cu(UO2)2(PO4)2 · 8H2O
Group 9 - Silicates
Almandine9.AD.25Fe2+3Al2(SiO4)3
Spessartine ?9.AD.25Mn2+3Al2(SiO4)3
Zircon9.AD.30Zr(SiO4)
Staurolite9.AF.30Fe2+2Al9Si4O23(OH)
Uranophane9.AK.15Ca(UO2)2(SiO3OH)2 · 5H2O
Beryl9.CJ.05Be3Al2(Si6O18)
Foitite ?9.CK.05◻(Fe2+2Al)Al6(Si6O18)(BO3)3(OH)3(OH)
Schorl9.CK.05NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
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 AutuniteCa(UO2)2(PO4)2 · 10-12H2O
H Foitite◻(Fe22+Al)Al6(Si6O18)(BO3)3(OH)3(OH)
H GoethiteFe3+O(OH)
H Opal var. Opal-ANSiO2 · nH2O
H Meta-autuniteCa(UO2)2(PO4)2 · 6H2O
H MetatorberniteCu(UO2)2(PO4)2 · 8H2O
H MuscoviteKAl2(AlSi3O10)(OH)2
H OpalSiO2 · nH2O
H SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
H StauroliteFe22+Al9Si4O23(OH)
H TorberniteCu(UO2)2(PO4)2 · 12H2O
H UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
BeBeryllium
Be BerylBe3Al2(Si6O18)
BBoron
B Foitite◻(Fe22+Al)Al6(Si6O18)(BO3)3(OH)3(OH)
B SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
CCarbon
C Bismutite(BiO)2CO3
OOxygen
O AlbiteNa(AlSi3O8)
O AnniteKFe32+(AlSi3O10)(OH)2
O AutuniteCa(UO2)2(PO4)2 · 10-12H2O
O AlmandineFe32+Al2(SiO4)3
O Bismutite(BiO)2CO3
O BerylBe3Al2(Si6O18)
O Columbite-(Fe)Fe2+Nb2O6
O Tantalite-(Fe)Fe2+Ta2O6
O Tapiolite-(Fe)Fe2+Ta2O6
O FluorapatiteCa5(PO4)3F
O Foitite◻(Fe22+Al)Al6(Si6O18)(BO3)3(OH)3(OH)
O GoethiteFe3+O(OH)
O Opal var. Opal-ANSiO2 · nH2O
O Meta-autuniteCa(UO2)2(PO4)2 · 6H2O
O MetatorberniteCu(UO2)2(PO4)2 · 8H2O
O MicroclineK(AlSi3O8)
O Monazite-(Ce)Ce(PO4)
O MuscoviteKAl2(AlSi3O10)(OH)2
O OpalSiO2 · nH2O
O QuartzSiO2
O Quartz var. Rose QuartzSiO2
O SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
O Quartz var. Smoky QuartzSiO2
O SpessartineMn32+Al2(SiO4)3
O StauroliteFe22+Al9Si4O23(OH)
O TorberniteCu(UO2)2(PO4)2 · 12H2O
O UraniniteUO2
O UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
O Yttrocolumbite-(Y)Y(U4+,Fe2+)Nb2O8
O ZirconZr(SiO4)
O Quartz var. Ferruginous QuartzSiO2
FFluorine
F FluorapatiteCa5(PO4)3F
NaSodium
Na AlbiteNa(AlSi3O8)
Na SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
AlAluminium
Al AlbiteNa(AlSi3O8)
Al AnniteKFe32+(AlSi3O10)(OH)2
Al AlmandineFe32+Al2(SiO4)3
Al BerylBe3Al2(Si6O18)
Al Foitite◻(Fe22+Al)Al6(Si6O18)(BO3)3(OH)3(OH)
Al MicroclineK(AlSi3O8)
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Al SpessartineMn32+Al2(SiO4)3
Al StauroliteFe22+Al9Si4O23(OH)
SiSilicon
Si AlbiteNa(AlSi3O8)
Si AnniteKFe32+(AlSi3O10)(OH)2
Si AlmandineFe32+Al2(SiO4)3
Si BerylBe3Al2(Si6O18)
Si Foitite◻(Fe22+Al)Al6(Si6O18)(BO3)3(OH)3(OH)
Si Opal var. Opal-ANSiO2 · nH2O
Si MicroclineK(AlSi3O8)
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si OpalSiO2 · nH2O
Si QuartzSiO2
Si Quartz var. Rose QuartzSiO2
Si SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Si Quartz var. Smoky QuartzSiO2
Si SpessartineMn32+Al2(SiO4)3
Si StauroliteFe22+Al9Si4O23(OH)
Si UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Si ZirconZr(SiO4)
Si Quartz var. Ferruginous QuartzSiO2
PPhosphorus
P AutuniteCa(UO2)2(PO4)2 · 10-12H2O
P FluorapatiteCa5(PO4)3F
P Meta-autuniteCa(UO2)2(PO4)2 · 6H2O
P MetatorberniteCu(UO2)2(PO4)2 · 8H2O
P Monazite-(Ce)Ce(PO4)
P TorberniteCu(UO2)2(PO4)2 · 12H2O
KPotassium
K AnniteKFe32+(AlSi3O10)(OH)2
K MicroclineK(AlSi3O8)
K MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Ca AutuniteCa(UO2)2(PO4)2 · 10-12H2O
Ca FluorapatiteCa5(PO4)3F
Ca Meta-autuniteCa(UO2)2(PO4)2 · 6H2O
Ca UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
MnManganese
Mn SpessartineMn32+Al2(SiO4)3
FeIron
Fe AnniteKFe32+(AlSi3O10)(OH)2
Fe AlmandineFe32+Al2(SiO4)3
Fe Columbite-(Fe)Fe2+Nb2O6
Fe Tantalite-(Fe)Fe2+Ta2O6
Fe Tapiolite-(Fe)Fe2+Ta2O6
Fe Foitite◻(Fe22+Al)Al6(Si6O18)(BO3)3(OH)3(OH)
Fe GoethiteFe3+O(OH)
Fe LöllingiteFeAs2
Fe SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Fe StauroliteFe22+Al9Si4O23(OH)
Fe Yttrocolumbite-(Y)Y(U4+,Fe2+)Nb2O8
CuCopper
Cu MetatorberniteCu(UO2)2(PO4)2 · 8H2O
Cu TorberniteCu(UO2)2(PO4)2 · 12H2O
AsArsenic
As LöllingiteFeAs2
YYttrium
Y Yttrocolumbite-(Y)Y(U4+,Fe2+)Nb2O8
ZrZirconium
Zr ZirconZr(SiO4)
NbNiobium
Nb Columbite-(Fe)Fe2+Nb2O6
Nb Yttrocolumbite-(Y)Y(U4+,Fe2+)Nb2O8
CeCerium
Ce Monazite-(Ce)Ce(PO4)
TaTantalum
Ta Tantalite-(Fe)Fe2+Ta2O6
Ta Tapiolite-(Fe)Fe2+Ta2O6
BiBismuth
Bi Bismutite(BiO)2CO3
UUranium
U AutuniteCa(UO2)2(PO4)2 · 10-12H2O
U Meta-autuniteCa(UO2)2(PO4)2 · 6H2O
U MetatorberniteCu(UO2)2(PO4)2 · 8H2O
U TorberniteCu(UO2)2(PO4)2 · 12H2O
U UraniniteUO2
U UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
U Yttrocolumbite-(Y)Y(U4+,Fe2+)Nb2O8

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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