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Keystone Trap Rock Quarry, Cornog, Wallace Township, Chester County, Pennsylvania, USAi
Regional Level Types
Keystone Trap Rock QuarryQuarry (Flooded)
CornogVillage
Wallace TownshipTownship
Chester CountyCounty
PennsylvaniaState
USACountry

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Latitude & Longitude (WGS84):
40° 4' 36'' North , 75° 44' 53'' West
Latitude & Longitude (decimal):
Type:
Quarry (Flooded) - last checked 2020
Köppen climate type:
Nearest Settlements:
PlacePopulationDistance
Eagleview1,644 (2017)6.1km
Lionville6,189 (2017)7.9km
Downingtown7,946 (2017)8.7km
Thorndale3,407 (2017)9.3km
Caln1,519 (2017)9.9km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Tuscarora Lapidary SocietyBrookhaven, Pennsylvania39km
Delaware Mineralogical Society, Inc.Wilmington, Delaware41km
Friends of Mineralogy - Pennsylvania ChapterSt. Peters, Pennsylvania49km
Mindat Locality ID:
4074
Long-form identifier:
mindat:1:2:4074:0
GUID (UUID V4):
0


A crushed stone quarry in Precambrian (Grenville) amphibolite gneiss within the Honeybrook uplift. The mineral assemblages for which this locality is well known, are the product of alpine cleft type hydrothermal recrystallization.

Operations started in 1907, but the quarry is now (2014) waterfilled.

According to https://www.bigswings.com/everything-know-cornog-quarry-pa/ (dated March 24, 2017) the quarry is fenced and guarded and entry is prohibited.

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


20 valid minerals.

Detailed Mineral List:

Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Albite
Formula: Na(AlSi3O8)
'Allanite Group'
Formula: (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
'Amphibole Supergroup'
Formula: AB2C5(T8O22)W2
Habit: Long hair-like, fiberous
Colour: pale to deep green
Fluorescence: none
Description: Tremolite, Variety Byssolite occurs in long hairlike fiberous masses, closely associated with crystalized Prehnite and Clinozoisite at this site.
'Amphibole Supergroup var. Byssolite'
Formula: AX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Habit: Long hair-like, fiberous
Colour: pale to deep green
Fluorescence: none
Description: Tremolite, Variety Byssolite occurs in long hairlike fiberous masses, closely associated with crystalized Prehnite and Clinozoisite at this site.
Ancylite-(Ce)
Formula: CeSr(CO3)2(OH) · H2O
Axinite-(Fe)
Formula: Ca2Fe2+Al2BSi4O15OH
Calcioancylite-(Ce)
Formula: (Ce,Ca,Sr)CO3(OH,H2O)
Calcite
Formula: CaCO3
Chalcopyrite
Formula: CuFeS2
'Chlorite Group'
Clinozoisite
Formula: (CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
Habit: Prismatic, somewhat rectangular in cross section, rarely terminated
Colour: greenish qrey to pale greyish brown
Description: Early in the 1950's Excellent crystals were being collected in amphibolite gneiss at this location. crystals ranging from minute needles to stout prismatic crystals six inches long to one inch across. In 1960, the first accurate identification of Clinozoisite in PA was made by D. M. Lapham, PA. Geo. Survey, using specimens from this site.
Dravite
Formula: NaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Fluorapatite
Formula: Ca5(PO4)3F
Galena
Formula: PbS
'Garnet Group'
Formula: X3Z2(SiO4)3
Goethite
Formula: Fe3+O(OH)
Gypsum
Formula: CaSO4 · 2H2O
'Hornblende Root Name Group'
Formula: ◻Ca2(C2+4C3+)(AlSi7O22)W2
'K Feldspar'
'K Feldspar var. Adularia'
Formula: KAlSi3O8
'Limonite'
Description: Pseudomorphs after pyrite
Prehnite
Formula: Ca2Al2Si3O10(OH)2
Pyrite
Formula: FeS2
Pyrrhotite
Formula: Fe1-xS
Quartz
Formula: SiO2
Quartz var. Smoky Quartz
Formula: SiO2
Schorl
Formula: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
Titanite
Formula: CaTi(SiO4)O
Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2
Habit: Long hair-like, fiberous
Colour: pale to deep green
Description: Tremolite, Variety Byssolite occurs in long hairlike fiberous masses, closely associated with crystalized Prehnite and Clinozoisite at this site.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
Chalcopyrite2.CB.10aCuFeS2
Pyrrhotite2.CC.10Fe1-xS
Galena2.CD.10PbS
Pyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
Goethite4.00.Fe3+O(OH)
Quartz4.DA.05SiO2
var. Smoky Quartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
Calcite5.AB.05CaCO3
Ancylite-(Ce)5.DC.05CeSr(CO3)2(OH) · H2O
Calcioancylite-(Ce)5.DC.05(Ce,Ca,Sr)CO3(OH,H2O)
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
Gypsum7.CD.40CaSO4 · 2H2O
Group 8 - Phosphates, Arsenates and Vanadates
Fluorapatite8.BN.05Ca5(PO4)3F
Group 9 - Silicates
Titanite9.AG.15CaTi(SiO4)O
Axinite-(Fe)9.BD.20Ca2Fe2+Al2BSi4O15OH
Clinozoisite9.BG.05a(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
Dravite9.CK.05NaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Schorl9.CK.05NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
Actinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Tremolite9.DE.10◻Ca2Mg5(Si8O22)(OH)2
Prehnite9.DP.20Ca2Al2Si3O10(OH)2
Albite9.FA.35Na(AlSi3O8)
Unclassified
'K Feldspar
var. Adularia'
-KAlSi3O8
'Amphibole Supergroup'-AB2C5(T8O22)W2
'Chlorite Group'-
'Limonite'-
'Hornblende Root Name Group'-◻Ca2(C2+4C3+)(AlSi7O22)W2
'K Feldspar'-
'Garnet Group'-X3Z2(SiO4)3
'Amphibole Supergroup
var. Byssolite'
-AX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
'Allanite Group'-(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)

List of minerals for each chemical element

HHydrogen
H Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
H Ancylite-(Ce)CeSr(CO3)2(OH) · H2O
H Calcioancylite-(Ce)(Ce,Ca,Sr)CO3(OH,H2O)
H Clinozoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
H DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
H Axinite-(Fe)Ca2Fe2+Al2BSi4O15OH
H GoethiteFe3+O(OH)
H GypsumCaSO4 · 2H2O
H PrehniteCa2Al2Si3O10(OH)2
H SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
H Tremolite◻Ca2Mg5(Si8O22)(OH)2
H Amphibole Supergroup var. ByssoliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
H Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
BBoron
B DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
B Axinite-(Fe)Ca2Fe2+Al2BSi4O15OH
B SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
CCarbon
C Ancylite-(Ce)CeSr(CO3)2(OH) · H2O
C Calcioancylite-(Ce)(Ce,Ca,Sr)CO3(OH,H2O)
C CalciteCaCO3
OOxygen
O Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
O K Feldspar var. AdulariaKAlSi3O8
O AlbiteNa(AlSi3O8)
O Amphibole SupergroupAB2C5(T8O22)W2
O Ancylite-(Ce)CeSr(CO3)2(OH) · H2O
O Calcioancylite-(Ce)(Ce,Ca,Sr)CO3(OH,H2O)
O CalciteCaCO3
O Clinozoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
O DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
O Axinite-(Fe)Ca2Fe2+Al2BSi4O15OH
O FluorapatiteCa5(PO4)3F
O GoethiteFe3+O(OH)
O GypsumCaSO4 · 2H2O
O PrehniteCa2Al2Si3O10(OH)2
O QuartzSiO2
O SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
O Quartz var. Smoky QuartzSiO2
O TitaniteCaTi(SiO4)O
O Tremolite◻Ca2Mg5(Si8O22)(OH)2
O Hornblende Root Name Group◻Ca2(C42+C3+)(AlSi7O22)W2
O Garnet GroupX3Z2(SiO4)3
O Amphibole Supergroup var. ByssoliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
O Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
FFluorine
F FluorapatiteCa5(PO4)3F
F Amphibole Supergroup var. ByssoliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
NaSodium
Na AlbiteNa(AlSi3O8)
Na DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Na SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
MgMagnesium
Mg Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Mg DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Mg Tremolite◻Ca2Mg5(Si8O22)(OH)2
AlAluminium
Al K Feldspar var. AdulariaKAlSi3O8
Al AlbiteNa(AlSi3O8)
Al Clinozoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
Al DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Al Axinite-(Fe)Ca2Fe2+Al2BSi4O15OH
Al PrehniteCa2Al2Si3O10(OH)2
Al SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Al Hornblende Root Name Group◻Ca2(C42+C3+)(AlSi7O22)W2
Al Amphibole Supergroup var. ByssoliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
SiSilicon
Si Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Si K Feldspar var. AdulariaKAlSi3O8
Si AlbiteNa(AlSi3O8)
Si Clinozoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
Si DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Si Axinite-(Fe)Ca2Fe2+Al2BSi4O15OH
Si PrehniteCa2Al2Si3O10(OH)2
Si QuartzSiO2
Si SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Si Quartz var. Smoky QuartzSiO2
Si TitaniteCaTi(SiO4)O
Si Tremolite◻Ca2Mg5(Si8O22)(OH)2
Si Hornblende Root Name Group◻Ca2(C42+C3+)(AlSi7O22)W2
Si Garnet GroupX3Z2(SiO4)3
Si Amphibole Supergroup var. ByssoliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Si Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
PPhosphorus
P FluorapatiteCa5(PO4)3F
SSulfur
S ChalcopyriteCuFeS2
S GalenaPbS
S GypsumCaSO4 · 2H2O
S PyriteFeS2
S PyrrhotiteFe1-xS
ClChlorine
Cl Amphibole Supergroup var. ByssoliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
KPotassium
K K Feldspar var. AdulariaKAlSi3O8
CaCalcium
Ca Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Ca Calcioancylite-(Ce)(Ce,Ca,Sr)CO3(OH,H2O)
Ca CalciteCaCO3
Ca Clinozoisite(CaCa)(AlAlAl)O[Si2O7][SiO4](OH)
Ca Axinite-(Fe)Ca2Fe2+Al2BSi4O15OH
Ca FluorapatiteCa5(PO4)3F
Ca GypsumCaSO4 · 2H2O
Ca PrehniteCa2Al2Si3O10(OH)2
Ca TitaniteCaTi(SiO4)O
Ca Tremolite◻Ca2Mg5(Si8O22)(OH)2
Ca Hornblende Root Name Group◻Ca2(C42+C3+)(AlSi7O22)W2
TiTitanium
Ti TitaniteCaTi(SiO4)O
Ti Amphibole Supergroup var. ByssoliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
FeIron
Fe Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Fe ChalcopyriteCuFeS2
Fe Axinite-(Fe)Ca2Fe2+Al2BSi4O15OH
Fe GoethiteFe3+O(OH)
Fe PyriteFeS2
Fe PyrrhotiteFe1-xS
Fe SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
CuCopper
Cu ChalcopyriteCuFeS2
SrStrontium
Sr Ancylite-(Ce)CeSr(CO3)2(OH) · H2O
Sr Calcioancylite-(Ce)(Ce,Ca,Sr)CO3(OH,H2O)
CeCerium
Ce Ancylite-(Ce)CeSr(CO3)2(OH) · H2O
Ce Calcioancylite-(Ce)(Ce,Ca,Sr)CO3(OH,H2O)
PbLead
Pb GalenaPbS

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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