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Brighton Dam Road Quarry (Howard-Montgomery Quarry), Howard County, Maryland, USAi
Regional Level Types
Brighton Dam Road Quarry (Howard-Montgomery Quarry)Quarry
Howard CountyCounty
MarylandState
USACountry

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PhotosMapsSearch
01586910017272012989673.jpg
Pyrite

Brighton Dam Road Quarry, Howard County, Maryland, USA
04856790017272013005704.jpg
Rutile

Brighton Dam Road Quarry, Howard County, Maryland, USA
02491070017272013029119.jpg
Pyrite

Brighton Dam Road Quarry, Howard County, Maryland, USA
01586910017272012989673.jpg
Pyrite

Brighton Dam Road Quarry, Howard County, Maryland, USA
04856790017272013005704.jpg
Rutile

Brighton Dam Road Quarry, Howard County, Maryland, USA
02491070017272013029119.jpg
Pyrite

Brighton Dam Road Quarry, Howard County, Maryland, USA
00399140017272013151000.jpg
Pyrite

Brighton Dam Road Quarry, Howard County, Maryland, USA
04856790017272013005704.jpg
Rutile

Brighton Dam Road Quarry, Howard County, Maryland, USA
Latitude & Longitude (WGS84):
39° 11' 44'' North , 76° 59' 9'' West
Latitude & Longitude (decimal):
39.19556,-76.98583
GRN:
N27W43
Type:
Quarry
Köppen climate type:
Cfa : Humid subtropical climate
Nearest Settlements:
PlacePopulationDistance
Highland1,034 (2011)3.1km
Ashton-Sandy Spring5,628 (2011)5.4km
Brookeville139 (2018)6.5km
Fulton2,049 (2011)7.3km
Olney33,844 (2011)8.4km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Gem, Lapidary, and Mineral Society of Montgomery County, MD., Inc.Rockville, Maryland19km
Central Maryland Rock and Mineral Collectors ExchangeElkridge, Maryland24km
Baltimore Mineral SocietyBaltimore, Maryland34km
Chesapeake Gem & Mineral SocietyBaltimore, Maryland34km
Gem Cutters Guild of Baltimore, Inc.Baltimore, Maryland34km
Mindat Locality ID:
3821
Long-form identifier:
mindat:1:2:3821:1
GUID (UUID V4):
0


This quarry was in a somewhat schistose to gneissic phase of the Cockeysville Marble along the southern flank of the Clarksville gneiss dome. It was operated by the Howard-Montgomery Crushed Stone Company, a division of Contee Sand and Gravel. The Howard/Montgomery Quarry is now filled with water and is located in the middle of an upscale residential neighborhood. The grounds of the quarry are posted "No Trespassing."



Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


14 valid minerals.

Detailed Mineral List:

ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Calcite
Formula: CaCO3
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ 'Chlorite Group'
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ Dravite
Formula: NaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
ⓘ 'Feldspar Group'
ⓘ 'K Feldspar'
ⓘ 'K Feldspar var. Adularia'
Formula: KAlSi3O8
ⓘ 'Limonite'
ⓘ Mackinawite
Formula: FeS
Description: with pyrrhotite
ⓘ Malachite
Formula: Cu2(CO3)(OH)2
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
ⓘ 'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2
ⓘ Rutile
Formula: TiO2
ⓘ 'Scapolite'
ⓘ Talc
Formula: Mg3Si4O10(OH)2
ⓘ Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘMackinawite2.CC.25FeS
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
ⓘRutile4.DB.05TiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘDolomite5.AB.10CaMg(CO3)2
ⓘMalachite5.BA.10Cu2(CO3)(OH)2
Group 9 - Silicates
ⓘDravite9.CK.05NaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
ⓘTremolite9.DE.10◻Ca2Mg5(Si8O22)(OH)2
ⓘTalc9.EC.05Mg3Si4O10(OH)2
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘPhlogopite9.EC.20KMg3(AlSi3O10)(OH)2
Unclassified
ⓘ'K Feldspar
var. Adularia'		-KAlSi3O8
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Chlorite Group'-
ⓘ'Feldspar Group'-
ⓘ'Limonite'-
ⓘ'Scapolite'-
ⓘ'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8
ⓘ'K Feldspar'-

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ⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Hⓘ MalachiteCu2(CO3)(OH)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Hⓘ TalcMg3Si4O10(OH)2
Hⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
BBoron
Bⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
CCarbon
Cⓘ CalciteCaCO3
Cⓘ DolomiteCaMg(CO3)2
Cⓘ MalachiteCu2(CO3)(OH)2
OOxygen
Oⓘ K Feldspar var. AdulariaKAlSi3O8
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ CalciteCaCO3
Oⓘ DolomiteCaMg(CO3)2
Oⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Oⓘ MalachiteCu2(CO3)(OH)2
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ RutileTiO2
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Oⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
NaSodium
Naⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Naⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ DolomiteCaMg(CO3)2
Mgⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Mgⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Mgⓘ TalcMg3Si4O10(OH)2
Mgⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
AlAluminium
Alⓘ K Feldspar var. AdulariaKAlSi3O8
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Alⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SiSilicon
Siⓘ K Feldspar var. AdulariaKAlSi3O8
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Siⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SSulfur
Sⓘ ChalcopyriteCuFeS2
Sⓘ MackinawiteFeS
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
KPotassium
Kⓘ K Feldspar var. AdulariaKAlSi3O8
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ DolomiteCaMg(CO3)2
Caⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Caⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ RutileTiO2
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ ChalcopyriteCuFeS2
Feⓘ MackinawiteFeS
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
CuCopper
Cuⓘ ChalcopyriteCuFeS2
Cuⓘ MalachiteCu2(CO3)(OH)2

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

MESA Health and Safety Inspection Report January 31 & February 1, 1972.
Edwards, J. (1971) Directory of mineral producers in Maryland: Maryland Geological Survey Information Circular 11: 15.
Bernstein, Lawrence R. (1980) Minerals of the Washington, D.C. Area - Issue 5 of Educational series, Maryland Geological Survey. Department of Natural Resources, Maryland Geological Survey. p.1-148.
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