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Hamden, New Haven County, Connecticut, USAi
Regional Level Types
HamdenTown
New Haven CountyCounty
ConnecticutState
USACountry

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PhotosMapsSearch
02711960017482224928357.jpg
View of the Sleeping Giant's Lobotomy

Mount Carmel Trap Rock Quarry, Hamden, New Haven County, Connecticut, USA
08143550017481212811960.jpg
Southern Prospect Pit in 1984

Tallman Mine, Hamden, New Haven County, Connecticut, USA
03918020017481212821578.jpg
Middle Adit Mine Dumps

Tallman Mine, Hamden, New Haven County, Connecticut, USA
08484650017481228648337.jpg
View of the Sleeping Giant's Lobotomy

Mount Carmel Trap Rock Quarry, Hamden, New Haven County, Connecticut, USA
01741580017481211819987.jpg
Southern Prospect Pit in 1984

Tallman Mine, Hamden, New Haven County, Connecticut, USA
03619190017481211642975.jpg
Middle Adit Mine Dumps

Tallman Mine, Hamden, New Haven County, Connecticut, USA
08484650017481228648337.jpg
View of the Sleeping Giant's Lobotomy

Mount Carmel Trap Rock Quarry, Hamden, New Haven County, Connecticut, USA
08143550017481212811960.jpg
Southern Prospect Pit in 1984

Tallman Mine, Hamden, New Haven County, Connecticut, USA
Neighbouring regions:
Bethany, New Haven County, Connecticut, USA
Cheshire, New Haven County, Connecticut, USA
Type:
Town
Largest Settlements:
PlacePopulation
Hamden59,847 (2017)
Mindat Locality ID:
227484
Long-form identifier:
mindat:1:2:227484:6
GUID (UUID V4):
0


Originally settled in 1638 by European immigrants as part of New Haven, Hamden incorporated as a separate town in 1786.

The bedrock geology consists mostly of the generally poorly exposed Triassic New Haven Formation, an arkosic sandstone and conglomerate in the Hartford Mesozoic Basin. Prominent ridges along the west (West Rock), south (Pine, Mill, and East Rock), and northeast (Sleeping Giant) edges of town are underlain by the Jurassic West Rock Diabase sill/dike complex. A separate narrow diabase dike, the Jurassic Buttress Dike, cuts through town intermittently NNE-SSW from West Rock Tunnel to just west of Sleeping Giant.

In the 18th and 19th centuries, a few very large pure copper nuggets were found in glacial till or attached to arkosic bedrock. The largest was found in 1870 0.5 mile north of East Rock and weighed about 200 pounds (90 kg). It is held by the Yale Peabody Museum in New Haven and was formerly on display. Another one is at the Connecticut Museum of Mining and Mineral Science in Kent, Connecticut. A 90-pound (40 kg) one was found barely attached to bedrock in 1790 and was made into a bell for a church in New Haven.

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

14 valid minerals.

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Habit: massive in matrix, acicular to capillary in small vugs
Colour: grayish-green
Description: Microcrystals in small vugs in altered sandstone (perhaps derived from calcareous concretions) with epidote.
ⓘ Andradite
Formula: Ca3Fe3+2(SiO4)3
Habit: modified rhombic dodecahedrons
Colour: wine yellow
Description: "The Mill Rock garnets have a wine-yellow color, and a brilliant luster. The material available was much too scanty to admit of any chemical examination, but in view of their similarity of form and color, they may safely be referred to the variety topazolite." (Dana, 1877). They are a couple of mm across or less, associated with quartz.
✪ Andradite var. Topazolite
Formula: Ca3Fe3+2(SiO4)3
Habit: modified rhombic dodecahedrons
Colour: wine yellow
Description: "The Mill Rock garnets have a wine-yellow color, and a brilliant luster. The material available was much too scanty to admit of any chemical examination, but in view of their similarity of form and color, they may safely be referred to the variety topazolite." (Dana, 1877). They are a couple of mm across or less, associated with quartz.
ⓘ Bornite
Formula: Cu5FeS4
Habit: lumps and grains
Colour: black with iridescence
Description: Lumps and grains in breccia veins with calcite and quartz or as grains in arkose. Associated with malachite, chrysocolla and cuprite secondary/post-mine mineralization.
ⓘ Calcite
Formula: CaCO3
Habit: scalenohedral
Colour: colorless
Description: micro crystals on prehnite aggregates
ⓘ 'Chabazite'
ⓘ Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Habit: massive, coatings
Colour: blue-green
Description: Alteration of bornite, with malachite.
ⓘ Cuprite
Formula: Cu2O
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ Fluorapophyllite-(K)
Formula: KCa4(Si8O20)(F,OH) · 8H2O
Habit: bipyramidal and prismatic combos or tabular
Colour: colorless
Description: Typically small (<0.5 cm) crystals on prehnite, or tabular around 1 cm. Species ID based on analyses of multiple specimens from various Connecticut localities, which are all fluorapophyllite-(K).
ⓘ Hematite
Formula: Fe2O3
ⓘ Hematite var. Specularite
Formula: Fe2O3
Description: In the baked arkose below the contact with the diabase.
ⓘ 'Heulandite Subgroup'
Formula: (Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Habit: rhombohedral
Colour: colorless to fleshy red
Description: small colorless and large fleshy red rhombs.
ⓘ Laumontite
Formula: CaAl2Si4O12 · 4H2O
ⓘ Malachite
Formula: Cu2(CO3)(OH)2
Colour: green
Description: coatings on large copper nuggets
✪ Native Copper
Formula: Cu
Habit: massive
Colour: Coated with green malachite.
Description: A few very large nuggets found in glacial till or attached to arkosic bedrock. The largest was found in 1870 0.5 mile north of East Rock and weighed about 200 pounds (90 kg).
ⓘ Prehnite
Formula: Ca2Al2Si3O10(OH)2
Habit: botryoidal aggregates
Colour: pale green
ⓘ Quartz
Formula: SiO2
Habit: drusy
Colour: colorless
Description: Massive in breccia and veins in arkose and diabase with calcite and bornite, drusy crystals in open spaces and on joint surfaces.
ⓘ Quartz var. Amethyst
Formula: SiO2
Habit: massive
Colour: purple
Description: As thin veins of radiating but contacted crystals, probably in diabase. Fragments seen in spoils around pits along the dike.
References:
Harold Moritz observationsIdentified by Harold Moritz: Visual Identification
ⓘ 'Stilbite Subgroup'
Formula: M6-7[Al8-9Si27-28O72] · nH2O

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Copper1.AA.05Cu
Group 2 - Sulphides and Sulfosalts
ⓘBornite2.BA.15Cu5FeS4
Group 4 - Oxides and Hydroxides
ⓘCuprite4.AA.10Cu2O
ⓘHematite4.CB.05Fe2O3
ⓘvar. Specularite4.CB.05Fe2O3
ⓘQuartz
var. Amethyst		4.DA.05SiO2
ⓘ4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘMalachite5.BA.10Cu2(CO3)(OH)2
Group 9 - Silicates
ⓘAndradite9.AD.25Ca3Fe3+2(SiO4)3
ⓘvar. Topazolite9.AD.25Ca3Fe3+2(SiO4)3
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘPrehnite9.DP.20Ca2Al2Si3O10(OH)2
ⓘFluorapophyllite-(K)9.EA.15KCa4(Si8O20)(F,OH) · 8H2O
ⓘChrysocolla9.ED.20Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
ⓘLaumontite9.GB.10CaAl2Si4O12 · 4H2O
Unclassified
ⓘ'Chabazite'-
ⓘ'Heulandite Subgroup'-(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
ⓘ'Stilbite Subgroup'-M6-7[Al8-9Si27-28O72] · nH2O

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ Fluorapophyllite-(K)KCa4(Si8O20)(F,OH) · 8H2O
Hⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Hⓘ LaumontiteCaAl2Si4O12 · 4H2O
Hⓘ MalachiteCu2(CO3)(OH)2
Hⓘ PrehniteCa2Al2Si3O10(OH)2
Hⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
CCarbon
Cⓘ CalciteCaCO3
Cⓘ MalachiteCu2(CO3)(OH)2
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ Quartz var. AmethystSiO2
Oⓘ AndraditeCa3Fe23+(SiO4)3
Oⓘ CalciteCaCO3
Oⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Oⓘ CupriteCu2O
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ Fluorapophyllite-(K)KCa4(Si8O20)(F,OH) · 8H2O
Oⓘ HematiteFe2O3
Oⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Oⓘ LaumontiteCaAl2Si4O12 · 4H2O
Oⓘ MalachiteCu2(CO3)(OH)2
Oⓘ PrehniteCa2Al2Si3O10(OH)2
Oⓘ QuartzSiO2
Oⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Oⓘ Hematite var. SpeculariteFe2O3
Oⓘ Andradite var. TopazoliteCa3Fe23+(SiO4)3
FFluorine
Fⓘ Fluorapophyllite-(K)KCa4(Si8O20)(F,OH) · 8H2O
NaSodium
Naⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
AlAluminium
Alⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Alⓘ LaumontiteCaAl2Si4O12 · 4H2O
Alⓘ PrehniteCa2Al2Si3O10(OH)2
Alⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ Quartz var. AmethystSiO2
Siⓘ AndraditeCa3Fe23+(SiO4)3
Siⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ Fluorapophyllite-(K)KCa4(Si8O20)(F,OH) · 8H2O
Siⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Siⓘ LaumontiteCaAl2Si4O12 · 4H2O
Siⓘ PrehniteCa2Al2Si3O10(OH)2
Siⓘ QuartzSiO2
Siⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Siⓘ Andradite var. TopazoliteCa3Fe23+(SiO4)3
SSulfur
Sⓘ BorniteCu5FeS4
KPotassium
Kⓘ Fluorapophyllite-(K)KCa4(Si8O20)(F,OH) · 8H2O
Kⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ AndraditeCa3Fe23+(SiO4)3
Caⓘ CalciteCaCO3
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ Fluorapophyllite-(K)KCa4(Si8O20)(F,OH) · 8H2O
Caⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Caⓘ LaumontiteCaAl2Si4O12 · 4H2O
Caⓘ PrehniteCa2Al2Si3O10(OH)2
Caⓘ Andradite var. TopazoliteCa3Fe23+(SiO4)3
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Feⓘ AndraditeCa3Fe23+(SiO4)3
Feⓘ BorniteCu5FeS4
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ HematiteFe2O3
Feⓘ Hematite var. SpeculariteFe2O3
Feⓘ Andradite var. TopazoliteCa3Fe23+(SiO4)3
CuCopper
Cuⓘ BorniteCu5FeS4
Cuⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Cuⓘ CupriteCu2O
Cuⓘ Native CopperCu
Cuⓘ MalachiteCu2(CO3)(OH)2

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/Hamden,_Connecticut
Wikidata ID:Q755271
GeoNames ID:4835665

Localities in this Region

USA

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North America PlateTectonic Plate

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