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Harford County, Maryland, USAi
Regional Level Types
Harford CountyCounty
MarylandState
USACountry

Coat of Arms of Harford CountyFlag of Harford County
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PhotosMapsSearchMineralogy
05755150017272056922367.jpg
Quarry Plant

Havre De Grace Quarry, Harford County, Maryland, USA
08481680017272056929986.jpg
Quarry

Churchville Quarry, Harford County, Maryland, USA
05082740017272056931487.jpg
Pyrite

Harford County, Maryland, USA
05755150017272056922367.jpg
Quarry Plant

Havre De Grace Quarry, Harford County, Maryland, USA
08481680017272056929986.jpg
Quarry

Churchville Quarry, Harford County, Maryland, USA
05082740017272056931487.jpg
Pyrite

Harford County, Maryland, USA
05755150017272056922367.jpg
Quarry Plant

Havre De Grace Quarry, Harford County, Maryland, USA
08481680017272056929986.jpg
Quarry

Churchville Quarry, Harford County, Maryland, USA
Neighbouring regions:
Lancaster County, Pennsylvania, USA
Baltimore County, Maryland, USA
Cecil County, Maryland, USA
York County, Pennsylvania, USA
Kent County, Maryland, USA
Type:
County
Largest Settlements:
PlacePopulation
South Bel Air48,828 (2010)
Bel Air South47,709 (2011)
North Bel Air33,925 (2010)
Bel Air North30,568 (2011)
Edgewood25,562 (2018)
Aberdeen15,580 (2017)
Mindat Locality ID:
26711
Long-form identifier:
mindat:1:2:26711:2
GUID (UUID V4):
0
Other Languages:
View 37 more...
French:
comté de Harford, Maryland, États-Unis
German:
Harford County, Maryland, Vereinigte Staaten
Italian:
contea di Harford, Maryland, Stati Uniti d'America
Russian:
Харфорд, Мэриленд, Соединённые Штаты Америки
Simplified Chinese:
哈福德縣 , 马里兰州, 美国
Spanish:
Condado de Harford, Maryland, Estados Unidos
Albanian:
Harford County, Maryland, Shtetet e Bashkuara të Amerikës
Arabic:
مقاطعة هارفورد, ماريلند, الولايات المتحدة
Armenian:
Հարֆորդ շրջան, Մերիլենդ, Ամերիկայի Միացյալ Նահանգներ
Basque:
Harford konderria , Maryland
Bavarian:
Harford County, Maryland, Vaoanigte Stootn
Belarusian:
акруга Харфард, Мэрыленд, Злучаныя Штаты Амерыкі
Bishnupriya Manipuri:
হারফোর্ড কাউন্টি, মেরিল্যান্ড, তিলপারাষ্ট্র
Bulgarian:
Хартфорд, Мериленд, Съединени американски щати
Cebuano:
Harford County, Maryland
Cornish:
Konteth Harford, Tir Maria, Statys Unys
Danish:
Harford County, Maryland, USA
Dutch:
Harford County, Maryland, Verenigde Staten
Farsi/Persian:
شهرستان فرودگاه، مریلند, مریلند, ایالات متحده آمریکا
Georgian:
ჰარფორდის ოლქი, მერილენდი, ამერიკის შეერთებული შტატები
Hebrew:
מחוז הרפורד, מרילנד, ארצות הברית
Hungarian:
Harford megye, Maryland, Amerikai Egyesült Államok
Indonesian:
Harford County, Maryland, Amerika Serikat
Japanese:
ハーフォード郡, メリーランド州, アメリカ合衆国
Low Saxon/Low German:
Harford County, Maryland, USA
Min Dong Chinese:
Harford Gông, Maryland
Minnan / Hokkien-Taiwanese:
Harford Kūn
Norwegian:
Harford County, Maryland, USA
Polish:
Hrabstwo Harford, Maryland, Stany Zjednoczone
Portuguese:
Condado de Harford, Maryland, Estados Unidos
Romanian:
Comitatul Harford, Maryland, Statele Unite ale Americii
Sardinian:
contea de Harford, Maryland, Istados Unidos de Amèrica
Scottish Gaelic:
Harford County, Maryland, Na Stàitean Aonaichte
Serbian:
Округ Харфорд , Мериленд, Сједињене Америчке Државе
Serbo-Croatian:
Harford County, Maryland, Sjedinjene Američke Države
Swedish:
Harford County, Maryland, USA
Traditional Chinese:
哈福德縣, 馬利蘭州, 美國
Turkish:
Harford County, Maryland, Amerika Birleşik Devletleri
Ukrainian:
Гарфорд, Меріленд, Сполучені Штати Америки
Urdu:
ہارفورڈ کاؤنٹی، میری لینڈ, میری لینڈ, ریاستہائے متحدہ امریکا
Waray:
Condado han Harford, Maryland, Estados Unidos
Welsh:
Sir Harford, Maryland, Unol Daleithiau America
Western Punjabi:
ہارفورڈ کاؤنٹی, میری لینڈ, امریکہ


Harford County is mostly underlain by complex igneous and metamorphic rocks of the Piedmont Province. This includes schists, gneiss and amphibolites of metasedimentary and metavolcanic origin, various granites and rocks of the Cambrian Baltimore Mafic Complex. All of the Piedmont rocks were caught up and deformed in the Ordovician Taconic Orogeny. These rocks are well exposed along the Susquehanna River gorge around Conowingo Dam and in several state parks. At Rocks State Park are good outcrops of schist and metaconglomerate. Palmer State Park features exposures of the Baltimore Gabbro complex. Serpentinite masses, often intruded by odd desilicified albitite dikes have provided some production of feldspar, decorative serpentinite and chromite, generally pre-1914. Lower grade metamorphic rock of the Peach Bottom slate were produced along the north and northwest edge of the County. The southern part of Harford County (generally south of I-95) is underlain by loosely consolidated Cretaceous, Tertiary and Quaternary sediments of the Coastal Plain Province.

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

35 valid minerals.

Rock Types Recorded


Rock list contains entries from the region specified including sub-localities

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ Albite var. Oligoclase
Formula: (Na,Ca)[Al(Si,Al)Si2O8]
ⓘ Ankerite
Formula: Ca(Fe2+,Mg)(CO3)2
ⓘ Anthophyllite
Formula: ◻Mg2Mg5(Si8O22)(OH)2
ⓘ Antigorite
Formula: Mg3(Si2O5)(OH)4
ⓘ Antigorite var. Williamsite
Formula: Mg3(Si2O5)(OH)4
ⓘ 'Apatite'
Formula: Ca5(PO4)3A
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Brucite
Formula: Mg(OH)2
ⓘ Calcite
Formula: CaCO3
ⓘ 'Chabazite'
References:
Stuart Herring
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ 'Chlorite Group'
Localities: Reported from at least 7 localities in this region.
ⓘ Chromite
Formula: Fe2+Cr3+2O4
Localities: Reported from at least 6 localities in this region.
ⓘ Chrysotile
Formula: Mg3(Si2O5)(OH)4
ⓘ Clinochlore
Formula: Mg5Al(AlSi3O10)(OH)8
ⓘ Clinochlore var. Chromium-bearing Clinochlore
Formula: Mg5(Al,Cr)2Si3O10(OH)8
ⓘ Clinochlore var. Ripidolite
Formula: (Mg,Fe,Al)6(Si,Al)4O10(OH)8
ⓘ Diopside
Formula: CaMgSi2O6
References:
Stuart Herring
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ Enstatite
Formula: Mg2Si2O6
ⓘ Enstatite var. Bronzite
Formula: (Mg,Fe2+)2[SiO3]2
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ 'Feldspar Group'
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ 'Garnierite'
ⓘ Goethite
Formula: Fe3+O(OH)
ⓘ Hematite
Formula: Fe2O3
ⓘ 'Heulandite Subgroup'
Formula: (Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Habit: Druzy coating
Colour: orange
ⓘ 'Hypersthene'
Formula: (Mg,Fe)SiO3
ⓘ Ilmenite
Formula: Fe2+TiO3
ⓘ Kyanite
Formula: Al2(SiO4)O
ⓘ Laumontite
Formula: CaAl2Si4O12 · 4H2O
ⓘ 'Limonite'
ⓘ Magnesite
Formula: MgCO3
ⓘ Magnesite var. Breunnerite
Formula: (Mg,Fe)CO3
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
Localities: Reported from at least 8 localities in this region.
ⓘ Opal
Formula: SiO2 · nH2O
ⓘ Opal var. Opal-AN
Formula: SiO2 · nH2O
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Quartz
Formula: SiO2
Localities: Reported from at least 7 localities in this region.
ⓘ Quartz var. Chalcedony
Formula: SiO2
ⓘ Quartz var. Moss Agate
Formula: SiO2
ⓘ Quartz var. Smoky Quartz
Formula: SiO2
ⓘ Rutile
Formula: TiO2
ⓘ Scolecite
Formula: CaAl2Si3O10 · 3H2O
References:
Jonathan Harris
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
Localities: Reported from at least 10 localities in this region.
ⓘ 'Serpentine Subgroup var. Picrolite'
Formula: D3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
ⓘ Sphalerite
Formula: ZnS
ⓘ Staurolite
Formula: Fe2+2Al9Si4O23(OH)
ⓘ 'Stilbite Subgroup'
Formula: M6-7[Al8-9Si27-28O72] · nH2O
References:
Stuart Herring
ⓘ Talc
Formula: Mg3Si4O10(OH)2
Localities: Reported from at least 8 localities in this region.
ⓘ Titanite
Formula: CaTiO(SiO4)
ⓘ 'Tourmaline'
Formula: AD3G6(T6O18)(BO3)3X3Z
ⓘ Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2
ⓘ Vermiculite
Formula: Mg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
ⓘ 'Wad'
ⓘ Zircon
Formula: Zr(SiO4)

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘSphalerite2.CB.05aZnS
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘGoethite4.00.Fe3+O(OH)
ⓘChromite4.BB.05Fe2+Cr3+2O4
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘHematite4.CB.05Fe2O3
ⓘIlmenite4.CB.05Fe2+TiO3
ⓘQuartz
var. Chalcedony		4.DA.05SiO2
ⓘvar. Moss Agate4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
ⓘOpal
var. Opal-AN		4.DA.10SiO2 · nH2O
ⓘ4.DA.10SiO2 · nH2O
ⓘRutile4.DB.05TiO2
ⓘBrucite4.FE.05Mg(OH)2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘMagnesite5.AB.05MgCO3
ⓘvar. Breunnerite5.AB.05(Mg,Fe)CO3
ⓘAnkerite5.AB.10Ca(Fe2+,Mg)(CO3)2
ⓘDolomite5.AB.10CaMg(CO3)2
Group 9 - Silicates
ⓘChrysotile9.00.Mg3(Si2O5)(OH)4
ⓘZircon9.AD.30Zr(SiO4)
ⓘKyanite9.AF.15Al2(SiO4)O
ⓘStaurolite9.AF.30Fe2+2Al9Si4O23(OH)
ⓘTitanite9.AG.15CaTiO(SiO4)
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘEnstatite9.DA.05Mg2Si2O6
ⓘvar. Bronzite9.DA.05(Mg,Fe2+)2[SiO3]2
ⓘDiopside9.DA.15CaMgSi2O6
ⓘAnthophyllite9.DD.05◻Mg2Mg5(Si8O22)(OH)2
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘTremolite9.DE.10◻Ca2Mg5(Si8O22)(OH)2
ⓘTalc9.EC.05Mg3Si4O10(OH)2
ⓘVermiculite9.EC.50Mg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
ⓘClinochlore9.EC.55Mg5Al(AlSi3O10)(OH)8
ⓘvar. Chromium-bearing Clinochlore9.EC.55Mg5(Al,Cr)2Si3O10(OH)8
ⓘvar. Ripidolite9.EC.55(Mg,Fe,Al)6(Si,Al)4O10(OH)8
ⓘAntigorite9.ED.15Mg3(Si2O5)(OH)4
ⓘvar. Williamsite9.ED.15Mg3(Si2O5)(OH)4
ⓘAlbite9.FA.35Na(AlSi3O8)
ⓘvar. Oligoclase9.FA.35(Na,Ca)[Al(Si,Al)Si2O8]
ⓘScolecite9.GA.05CaAl2Si3O10 · 3H2O
ⓘLaumontite9.GB.10CaAl2Si4O12 · 4H2O
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Chabazite'-
ⓘ'Chlorite Group'-
ⓘ'Feldspar Group'-
ⓘ'Heulandite Subgroup'-(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
ⓘ'Hypersthene'-(Mg,Fe)SiO3
ⓘ'Limonite'-
ⓘ'Stilbite Subgroup'-M6-7[Al8-9Si27-28O72] · nH2O
ⓘ'Tourmaline'-AD3G6(T6O18)(BO3)3X3Z
ⓘ'Wad'-
ⓘ'Garnet Group'-X3Z2(SiO4)3
ⓘ'Garnierite'-
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4
ⓘ'var. Picrolite'-D3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
ⓘ'Apatite'-Ca5(PO4)3A

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ Anthophyllite◻Mg2Mg5(Si8O22)(OH)2
Hⓘ AntigoriteMg3(Si2O5)(OH)4
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ BruciteMg(OH)2
Hⓘ ChrysotileMg3(Si2O5)(OH)4
Hⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ GoethiteFe3+O(OH)
Hⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Hⓘ Opal var. Opal-ANSiO2 · nH2O
Hⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Hⓘ LaumontiteCaAl2Si4O12 · 4H2O
Hⓘ OpalSiO2 · nH2O
Hⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Hⓘ ScoleciteCaAl2Si3O10 · 3H2O
Hⓘ StauroliteFe22+Al9Si4O23(OH)
Hⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Hⓘ TalcMg3Si4O10(OH)2
Hⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Hⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
Hⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
Hⓘ Antigorite var. WilliamsiteMg3(Si2O5)(OH)4
BBoron
Bⓘ TourmalineAD3G6(T6O18)(BO3)3X3Z
CCarbon
Cⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Cⓘ CalciteCaCO3
Cⓘ DolomiteCaMg(CO3)2
Cⓘ MagnesiteMgCO3
Cⓘ Magnesite var. Breunnerite(Mg,Fe)CO3
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Oⓘ Anthophyllite◻Mg2Mg5(Si8O22)(OH)2
Oⓘ AntigoriteMg3(Si2O5)(OH)4
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ BruciteMg(OH)2
Oⓘ CalciteCaCO3
Oⓘ Quartz var. ChalcedonySiO2
Oⓘ ChrysotileMg3(Si2O5)(OH)4
Oⓘ ChromiteFe2+Cr23+O4
Oⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Oⓘ DiopsideCaMgSi2O6
Oⓘ DolomiteCaMg(CO3)2
Oⓘ EnstatiteMg2Si2O6
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ GoethiteFe3+O(OH)
Oⓘ HematiteFe2O3
Oⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Oⓘ Opal var. Opal-ANSiO2 · nH2O
Oⓘ Hypersthene(Mg,Fe)SiO3
Oⓘ IlmeniteFe2+TiO3
Oⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Oⓘ KyaniteAl2(SiO4)O
Oⓘ LaumontiteCaAl2Si4O12 · 4H2O
Oⓘ MagnesiteMgCO3
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ Quartz var. Moss AgateSiO2
Oⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Oⓘ OpalSiO2 · nH2O
Oⓘ QuartzSiO2
Oⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Oⓘ RutileTiO2
Oⓘ ScoleciteCaAl2Si3O10 · 3H2O
Oⓘ Quartz var. Smoky QuartzSiO2
Oⓘ StauroliteFe22+Al9Si4O23(OH)
Oⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ TitaniteCaTiO(SiO4)
Oⓘ TourmalineAD3G6(T6O18)(BO3)3X3Z
Oⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Oⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Oⓘ ZirconZr(SiO4)
Oⓘ Enstatite var. Bronzite(Mg,Fe2+)2[SiO3]2
Oⓘ Magnesite var. Breunnerite(Mg,Fe)CO3
Oⓘ Garnet GroupX3Z2(SiO4)3
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
Oⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
Oⓘ Antigorite var. WilliamsiteMg3(Si2O5)(OH)4
Oⓘ ApatiteCa5(PO4)3A
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
Naⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Naⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Mgⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Mgⓘ Anthophyllite◻Mg2Mg5(Si8O22)(OH)2
Mgⓘ AntigoriteMg3(Si2O5)(OH)4
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ BruciteMg(OH)2
Mgⓘ ChrysotileMg3(Si2O5)(OH)4
Mgⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Mgⓘ DiopsideCaMgSi2O6
Mgⓘ DolomiteCaMg(CO3)2
Mgⓘ EnstatiteMg2Si2O6
Mgⓘ Hypersthene(Mg,Fe)SiO3
Mgⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Mgⓘ MagnesiteMgCO3
Mgⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Mgⓘ TalcMg3Si4O10(OH)2
Mgⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Mgⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Mgⓘ Enstatite var. Bronzite(Mg,Fe2+)2[SiO3]2
Mgⓘ Magnesite var. Breunnerite(Mg,Fe)CO3
Mgⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
Mgⓘ Antigorite var. WilliamsiteMg3(Si2O5)(OH)4
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Alⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Alⓘ KyaniteAl2(SiO4)O
Alⓘ LaumontiteCaAl2Si4O12 · 4H2O
Alⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Alⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Alⓘ ScoleciteCaAl2Si3O10 · 3H2O
Alⓘ StauroliteFe22+Al9Si4O23(OH)
Alⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Alⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Alⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Anthophyllite◻Mg2Mg5(Si8O22)(OH)2
Siⓘ AntigoriteMg3(Si2O5)(OH)4
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ ChrysotileMg3(Si2O5)(OH)4
Siⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Siⓘ DiopsideCaMgSi2O6
Siⓘ EnstatiteMg2Si2O6
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Siⓘ Opal var. Opal-ANSiO2 · nH2O
Siⓘ Hypersthene(Mg,Fe)SiO3
Siⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Siⓘ KyaniteAl2(SiO4)O
Siⓘ LaumontiteCaAl2Si4O12 · 4H2O
Siⓘ Quartz var. Moss AgateSiO2
Siⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Siⓘ OpalSiO2 · nH2O
Siⓘ QuartzSiO2
Siⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Siⓘ ScoleciteCaAl2Si3O10 · 3H2O
Siⓘ Quartz var. Smoky QuartzSiO2
Siⓘ StauroliteFe22+Al9Si4O23(OH)
Siⓘ Stilbite SubgroupM6-7[Al8-9Si27-28O72] · nH2O
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ TitaniteCaTiO(SiO4)
Siⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Siⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Siⓘ ZirconZr(SiO4)
Siⓘ Enstatite var. Bronzite(Mg,Fe2+)2[SiO3]2
Siⓘ Garnet GroupX3Z2(SiO4)3
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
Siⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
Siⓘ Antigorite var. WilliamsiteMg3(Si2O5)(OH)4
PPhosphorus
Pⓘ ApatiteCa5(PO4)3A
SSulfur
Sⓘ ChalcopyriteCuFeS2
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
Sⓘ SphaleriteZnS
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
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ⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Caⓘ CalciteCaCO3
Caⓘ DiopsideCaMgSi2O6
Caⓘ DolomiteCaMg(CO3)2
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ Heulandite Subgroup(Na/Ca/K)5-6[Al8-9 Si27-28 O72] · nH2O
Caⓘ LaumontiteCaAl2Si4O12 · 4H2O
Caⓘ Albite var. Oligoclase(Na,Ca)[Al(Si,Al)Si2O8]
Caⓘ ScoleciteCaAl2Si3O10 · 3H2O
Caⓘ TitaniteCaTiO(SiO4)
Caⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Caⓘ ApatiteCa5(PO4)3A
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ IlmeniteFe2+TiO3
Tiⓘ RutileTiO2
Tiⓘ TitaniteCaTiO(SiO4)
CrChromium
Crⓘ ChromiteFe2+Cr23+O4
Crⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
MnManganese
Mnⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Feⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ ChalcopyriteCuFeS2
Feⓘ ChromiteFe2+Cr23+O4
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ GoethiteFe3+O(OH)
Feⓘ HematiteFe2O3
Feⓘ Hypersthene(Mg,Fe)SiO3
Feⓘ IlmeniteFe2+TiO3
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
Feⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Feⓘ StauroliteFe22+Al9Si4O23(OH)
Feⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Feⓘ Enstatite var. Bronzite(Mg,Fe2+)2[SiO3]2
Feⓘ Magnesite var. Breunnerite(Mg,Fe)CO3
Feⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
NiNickel
Niⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
CuCopper
Cuⓘ ChalcopyriteCuFeS2
ZnZinc
Znⓘ SphaleriteZnS
Znⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
ZrZirconium
Zrⓘ ZirconZr(SiO4)

Fossils

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Other Databases

Wikipedia:https://en.wikipedia.org/wiki/Harford_County,_Maryland
Wikidata ID:Q501284
GeoNames ID:4357407

Localities in this Region

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Other Regions, Features and Areas that Intersect

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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

Pearre, N. & A. V. Heyl (1960) Mineral deposits in serpentine rocks of the Piedmont Upland, Maryland, Pennsylvania and Delaware: U. S. Geological Survey: Bulletin 1082K: 707-833.
Southwick, D. , J. Owens & J. Edwards (1969) The Geology of Harford County, Maryland: Maryland Geological Survey: County Report: 133 p.
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