Vote for your favorite mineral in #MinCup26! - Bournonite vs. Vesuvianite
Cogwheels of bournonite are up against colourful vesuvianite.
Log InRegister
Quick Links : The Mindat ManualThe Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsThe Rock H. Currier Digital LibraryGeologic TimeExplore Fossils
Minerals by PropertiesMinerals by ChemistryMineral Visual ExplorerAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral QuizTime Machine
Photo SearchPhoto GalleriesSearch by ColorPhoto Colour ExplorerNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Marriottsville Talc Quarries, Carroll County, Maryland, USAi
Regional Level Types
Marriottsville Talc QuarriesGroup of Mines
Carroll CountyCounty
MarylandState
USACountry

This page is currently not sponsored. Click here to sponsor this page.
PhotosMapsSearchMineralogy
Latitude & Longitude (WGS84):
39° 22' 1'' North , 76° 54' 42'' West
Latitude & Longitude (decimal):
39.36708,-76.91172
GRN:
N27W43
Type:
Group of Mines
Köppen climate type:
Cfa : Humid subtropical climate
Nearest Settlements:
PlacePopulationDistance
Sykesville4,412 (2017)4.9km
Eldersburg30,531 (2011)5.2km
Randallstown32,430 (2011)10.0km
Milford Mill29,042 (2011)12.4km
Owings Mills30,622 (2011)12.7km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Central Maryland Rock and Mineral Collectors ExchangeElkridge, Maryland24km
Baltimore Mineral SocietyBaltimore, Maryland27km
Chesapeake Gem & Mineral SocietyBaltimore, Maryland27km
Gem Cutters Guild of Baltimore, Inc.Baltimore, Maryland27km
Gem, Lapidary, and Mineral Society of Montgomery County, MD., Inc.Rockville, Maryland38km
Mindat Locality ID:
43628
Long-form identifier:
mindat:1:2:43628:0
GUID (UUID V4):
0


Talc was worked from several small pits in a schistose ultramafic rock near Marriottsville [Howard County], mostly near Piney Run {Carroll County].

"About a mile northwest of Marriottsville are two groups of talc quarries within a span of about a quarter of a mile where Piny Run crosses a long, narrow ultramafic body."

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


5 valid minerals.

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
References:
Stuart Herring
ⓘ 'Chlorite Group'
References:
Stuart Herring
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
References:
Stuart Herring
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
References:
Stuart Herring
ⓘ Pyrite
Formula: FeS2
References:
Stuart Herring
ⓘ Quartz
Formula: SiO2
References:
Stuart Herring
ⓘ Talc
Formula: Mg3Si4O10(OH)2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz4.DA.05SiO2
Group 9 - Silicates
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘTalc9.EC.05Mg3Si4O10(OH)2
Unclassified
ⓘ'Chlorite Group'-
ⓘ'Garnet Group'-X3Z2(SiO4)3

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ TalcMg3Si4O10(OH)2
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ QuartzSiO2
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ Garnet GroupX3Z2(SiO4)3
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Mgⓘ TalcMg3Si4O10(OH)2
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ QuartzSiO2
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ Garnet GroupX3Z2(SiO4)3
SSulfur
Sⓘ PyriteFeS2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2

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. & A. V. Heyl (1960) Mineral deposits in serpentine rocks of the Piedmont Upland, Maryland, Pennsylvania and Delaware: U. S. Geological Survey: Bulletin 1082K: 796 pp.
Pearre, Nancy C., (1961) Mineral deposits of Maryland, excluding fuels, sand, and gravel, plate 1: USGS Numbered Series Mineral resources and mined land inventory of Carroll County, Maryland.
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.
Quick NavTopCommoditiesMineral ListOther RegionsReferences
 
and/or  
Mindat.org® is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Mindat® and mindat.org® are registered trademarks of the Hudson Institute of Mineralogy.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2026, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph and Ida Chau.
Content on this site may not be used to train, fine-tune, or otherwise develop artificial intelligence or machine learning models without prior written permission - see our Terms & Conditions.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: September 4, 2026 11:49:13 Page updated: July 24, 2026 14:23:19
Go to top of page