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Patapsco Glen Construction Site, Woodlawn, Baltimore County, Maryland, USAi
Regional Level Types
Patapsco Glen Construction SiteConstruction Site (Built Over)
WoodlawnCensus-designated Place
Baltimore CountyCounty
MarylandState
USACountry

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PhotosMapsSearch
09809000017272438245584.jpg
Veiw from Johnnycake Rd

Patapsco Glen Construction Site, Woodlawn, Baltimore County, Maryland, USA
09809000017272438245584.jpg
Veiw from Johnnycake Rd

Patapsco Glen Construction Site, Woodlawn, Baltimore County, Maryland, USA
09809000017272438245584.jpg
Veiw from Johnnycake Rd

Patapsco Glen Construction Site, Woodlawn, Baltimore County, Maryland, USA
Latitude & Longitude (WGS84):
39° 18' 50'' North , 76° 46' 47'' West
Latitude & Longitude (decimal):
39.31408,-76.77982
GRN:
N27W43
Type:
Construction Site (Built Over) - last checked 2024
Deposit first discovered:
2020
Köppen climate type:
Cfa : Humid subtropical climate
Nearest Settlements:
PlacePopulationDistance
Milford Mill29,042 (2011)3.9km
Woodlawn37,879 (2011)4.6km
Ellicott City65,834 (2011)5.4km
Lochearn25,333 (2011)5.8km
Randallstown32,430 (2011)6.1km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Central Maryland Rock and Mineral Collectors ExchangeElkridge, Maryland13km
Baltimore Mineral SocietyBaltimore, Maryland15km
Chesapeake Gem & Mineral SocietyBaltimore, Maryland15km
Gem Cutters Guild of Baltimore, Inc.Baltimore, Maryland15km
Gem, Lapidary, and Mineral Society of Montgomery County, MD., Inc.Rockville, Maryland41km
Mindat Locality ID:
440784
Long-form identifier:
mindat:1:2:440784:6
GUID (UUID V4):
0


A construction site started in 2020 for homes located in the Hollofield Layered Ultramafite. The site is located on private property and is built over.
"The Hollofield Layered Ultramafite consists of ultramafic and mafic rocks inter layered on a scale that varies from centimeters to tens of meters. Chief among these is actinofels and actinoschist comprised almost entirely of light green actinolite, generally as a tangled mass of fine needles, but in places coarser-grained and having a more granular appearance. With the addition of plagioclase, actinofels grades into plagioclaseactinolite amphibolite (metagabbro of earlier workers). Such interlayered amphibolite, either actinolitic or hornblendic, and very rarely bearing garnet, comprises one-third of the exposed formation. Less common is bluishblack, orange-weathering serpentinite generally with subordinate amphibole (metaperidotite of earlier geologists). Chlorite may occur in any of these three rock types, either as discrete flakes or as schistose zones. Talc is locally associated with serpentinite, and tremolite and anthophyllite with actinofels. In places the rocks contain relict pyroxene and olivine which provide direct evidence of the igneous origin of the formation. Characteristically, the Hollofield consists chiefly of actinofels with subordinate interlayered amphibolite and serpentinite, but certain areas can be outlined where serpentinite predominates; such areas have been mapped separately."
(Ref: William P. Crowley, (1976) Department of Natural Resources, Maryland Geological Survey. Report of Investigations 27, The Geology of the crystalline rocks near Baltimore and its bearing on the evolution of the eastern Maryland Piedmont, page 13)
Link: http://www.mgs.md.gov/publications/report_pages/RI_27.html

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


10 valid minerals.

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Amphibole Supergroup'
Formula: AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Anthophyllite
Formula: ◻{Mg2}{Mg5}(Si8O22)(OH)2
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Calcite
Formula: CaCO3
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Chlorite Group'
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Deweylite'
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Feldspar Group'
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Forsterite
Formula: Mg2SiO4
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Forsterite var. Peridot
Formula: Mg2SiO4
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Manganese Oxides'
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Manganese Oxides var. Manganese Dendrites'
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Mica Group'
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Opal
Formula: SiO2 · nH2O
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Opal var. Opal-AN
Formula: SiO2 · nH2O
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Pyroxene Group'
Formula: ADSi2O6
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Quartz
Formula: SiO2
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Quartz var. Chalcedony
Formula: SiO2
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Talc
Formula: Mg3Si4O10(OH)2
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Titanite
Formula: CaTi(SiO4)O
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification
ⓘ Zircon
Formula: Zr(SiO4)
References:
Stuart Herring CollectionIdentified by Stuart Herring: Visual Identification

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz
var. Chalcedony		4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘOpal
var. Opal-AN		4.DA.10SiO2 · nH2O
ⓘ4.DA.10SiO2 · nH2O
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 9 - Silicates
ⓘForsterite9.AC.05Mg2SiO4
ⓘvar. Peridot9.AC.05Mg2SiO4
ⓘZircon9.AD.30Zr(SiO4)
ⓘTitanite9.AG.15CaTi(SiO4)O
ⓘAnthophyllite9.DD.05◻{Mg2}{Mg5}(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
Unclassified
ⓘ'Amphibole Supergroup'-AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ'Chlorite Group'-
ⓘ'Deweylite'-
ⓘ'Feldspar Group'-
ⓘ'Mica Group'-
ⓘ'Pyroxene Group'-ADSi2O6
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4
ⓘ'Manganese Oxides
var. Manganese Dendrites'		-
ⓘ''-

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Hⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Hⓘ Opal var. Opal-ANSiO2 · nH2O
Hⓘ OpalSiO2 · nH2O
Hⓘ TalcMg3Si4O10(OH)2
Hⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Oⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Oⓘ CalciteCaCO3
Oⓘ Quartz var. ChalcedonySiO2
Oⓘ ForsteriteMg2SiO4
Oⓘ Opal var. Opal-ANSiO2 · nH2O
Oⓘ OpalSiO2 · nH2O
Oⓘ QuartzSiO2
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ TitaniteCaTi(SiO4)O
Oⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Oⓘ ZirconZr(SiO4)
Oⓘ Forsterite var. PeridotMg2SiO4
Oⓘ Pyroxene GroupADSi2O6
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
FFluorine
Fⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Mgⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Mgⓘ ForsteriteMg2SiO4
Mgⓘ TalcMg3Si4O10(OH)2
Mgⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Mgⓘ Forsterite var. PeridotMg2SiO4
AlAluminium
Alⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Siⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ ForsteriteMg2SiO4
Siⓘ Opal var. Opal-ANSiO2 · nH2O
Siⓘ OpalSiO2 · nH2O
Siⓘ QuartzSiO2
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ TitaniteCaTi(SiO4)O
Siⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
Siⓘ ZirconZr(SiO4)
Siⓘ Forsterite var. PeridotMg2SiO4
Siⓘ Pyroxene GroupADSi2O6
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
ClChlorine
Clⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ CalciteCaCO3
Caⓘ TitaniteCaTi(SiO4)O
Caⓘ Tremolite◻Ca2Mg5(Si8O22)(OH)2
TiTitanium
Tiⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Tiⓘ TitaniteCaTi(SiO4)O
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ZrZirconium
Zrⓘ ZirconZr(SiO4)

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

William P. Crowley, (1976) Department of Natural Resources, Maryland Geological Survey. Report of Investigations 27, The Geology of the crystalline rocks near Baltimore and its bearing on the evolution of the eastern Maryland Piedmont, page 13
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