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Jarretsville-Dublin Mining District, Harford County, Maryland, USAi
Regional Level Types
Jarretsville-Dublin Mining District- not defined -
Harford CountyCounty
MarylandState
USACountry

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01262780017272023345537.jpg
Magnetite

Broad Creek Mine, Whiteford, Jarretsville-Dublin Mining District, Harford County, Maryland, USA
00689290017272023354430.jpg
Magnetite

Broad Creek Mine, Whiteford, Jarretsville-Dublin Mining District, Harford County, Maryland, USA
01262780017272023345537.jpg
Magnetite

Broad Creek Mine, Whiteford, Jarretsville-Dublin Mining District, Harford County, Maryland, USA
00689290017272023354430.jpg
Magnetite

Broad Creek Mine, Whiteford, Jarretsville-Dublin Mining District, Harford County, Maryland, USA
01262780017272023345537.jpg
Magnetite

Broad Creek Mine, Whiteford, Jarretsville-Dublin Mining District, Harford County, Maryland, USA
00689290017272023354430.jpg
Magnetite

Broad Creek Mine, Whiteford, Jarretsville-Dublin Mining District, Harford County, Maryland, USA
Latitude & Longitude (WGS84):
39° North , 76° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~32km
GRN:
N27W43
Köppen climate type:
Cfa : Humid subtropical climate
Mindat Locality ID:
307378
Long-form identifier:
mindat:1:2:307378:3
GUID (UUID V4):
0


Serpentine

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

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

12 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:

ⓘ 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
ⓘ Brucite
Formula: Mg(OH)2
ⓘ 'Chlorite Group'
ⓘ 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
ⓘ 'Garnierite'
ⓘ Magnesite
Formula: MgCO3
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Quartz
Formula: SiO2
ⓘ Quartz var. Chalcedony
Formula: SiO2
ⓘ Quartz var. Moss Agate
Formula: SiO2
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
Localities: Reported from at least 7 localities in this region.
ⓘ 'Serpentine Subgroup var. Picrolite'
Formula: D3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
ⓘ Talc
Formula: Mg3Si4O10(OH)2
ⓘ Vermiculite
Formula: Mg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘChromite4.BB.05Fe2+Cr3+2O4
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz
var. Chalcedony		4.DA.05SiO2
ⓘvar. Moss Agate4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘBrucite4.FE.05Mg(OH)2
Group 5 - Nitrates and Carbonates
ⓘMagnesite5.AB.05MgCO3
ⓘAnkerite5.AB.10Ca(Fe2+,Mg)(CO3)2
Group 9 - Silicates
ⓘChrysotile9.00.Mg3(Si2O5)(OH)4
ⓘAnthophyllite9.DD.05◻Mg2Mg5(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
Unclassified
ⓘ'Chlorite Group'-
ⓘ'Garnierite'-
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4
ⓘ'var. Picrolite'-D3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn

List of minerals for each chemical element

HHydrogen
Hⓘ Anthophyllite◻Mg2Mg5(Si8O22)(OH)2
Hⓘ AntigoriteMg3(Si2O5)(OH)4
Hⓘ BruciteMg(OH)2
Hⓘ ChrysotileMg3(Si2O5)(OH)4
Hⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Hⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Hⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Hⓘ TalcMg3Si4O10(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
CCarbon
Cⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Cⓘ MagnesiteMgCO3
OOxygen
Oⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Oⓘ Anthophyllite◻Mg2Mg5(Si8O22)(OH)2
Oⓘ AntigoriteMg3(Si2O5)(OH)4
Oⓘ BruciteMg(OH)2
Oⓘ Quartz var. ChalcedonySiO2
Oⓘ ChrysotileMg3(Si2O5)(OH)4
Oⓘ ChromiteFe2+Cr23+O4
Oⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Oⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Oⓘ MagnesiteMgCO3
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ Quartz var. Moss AgateSiO2
Oⓘ QuartzSiO2
Oⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
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
MgMagnesium
Mgⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Mgⓘ Anthophyllite◻Mg2Mg5(Si8O22)(OH)2
Mgⓘ AntigoriteMg3(Si2O5)(OH)4
Mgⓘ BruciteMg(OH)2
Mgⓘ ChrysotileMg3(Si2O5)(OH)4
Mgⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
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ⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Mgⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
Mgⓘ Antigorite var. WilliamsiteMg3(Si2O5)(OH)4
AlAluminium
Alⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Alⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Alⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
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ⓘ Anthophyllite◻Mg2Mg5(Si8O22)(OH)2
Siⓘ AntigoriteMg3(Si2O5)(OH)4
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ ChrysotileMg3(Si2O5)(OH)4
Siⓘ ClinochloreMg5Al(AlSi3O10)(OH)8
Siⓘ Clinochlore var. Chromium-bearing ClinochloreMg5(Al,Cr)2Si3O10(OH)8
Siⓘ Quartz var. Moss AgateSiO2
Siⓘ QuartzSiO2
Siⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
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
CaCalcium
Caⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
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ⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Feⓘ ChromiteFe2+Cr23+O4
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ Clinochlore var. Ripidolite(Mg,Fe,Al)6(Si,Al)4O10(OH)8
Feⓘ VermiculiteMg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
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
ZnZinc
Znⓘ Serpentine Subgroup var. PicroliteD3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn

Localities in this Region

USA
USA

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

Pearre, N. C.; Van Heyl, A. (1960) Chromite and other mineral deposits in serpentine rocks of the Piedmont Upland, Maryland, Pennsylvania, and Delaware. Bulletin 1082k. US Geological Survey doi:10.3133/b1082k pp.707-833
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