Maryland Mine (Allen shaft), Potomac, Montgomery County, Maryland, USAi
| Regional Level Types | |
|---|---|
| Maryland Mine (Allen shaft) | Mine |
| Potomac | Census-designated Place |
| Montgomery County | County |
| Maryland | State |
| USA | Country |
This page is currently not sponsored. Click here to sponsor this page.
Latitude & Longitude (WGS84):
38° 59' 44'' North , 77° 13' 53'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Potomac | 44,965 (2011) | 3.2km |
| Great Falls | 15,427 (2011) | 4.9km |
| Cabin John | 2,280 (2011) | 6.7km |
| Wolf Trap | 16,131 (2011) | 7.8km |
| Glen Echo | 272 (2017) | 8.2km |
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
Local clubs are the best way to get access to collecting localities
| Club | Location | Distance |
|---|---|---|
| Gem, Lapidary, and Mineral Society of Montgomery County, MD., Inc. | Rockville, Maryland | 12km |
| Northern Virginia Mineral Club, Inc. | Arlington, Virginia | 17km |
| Southern Maryland Rock and Mineral Club | Clinton, Maryland | 39km |
| American Fossil Federation | Bowie, Maryland | 44km |
| Maryland Geological Society | Bowie, Maryland | 44km |
A gold mine owned by the Maryland Gold Mining Co. Started about 1867 and last worked in 1951. The mine worked northerly trending quartz veins cutting schist and gneiss(meta-shale and meta-greywacke)of the Cambrian to Proterozoic Mather Gorge Formation, part of what was previously called the Wissahickon Formation. Workings featured a 210 foot (60 meter) deep shaft. Located about 1 mile east of Great Falls, south of the town of Potomac. Nagy and Parker (2013) present an excellent history of the mine and its minerals. The mine site is now in a National Historical Park.
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsDetailed Mineral List:
| ⓘ Ankerite Formula: Ca(Fe2+,Mg)(CO3)2 |
| ⓘ Arsenopyrite Formula: FeAsS |
| ⓘ Chalcopyrite Formula: CuFeS2 References: |
| ⓘ 'Chlorite Group' |
| ⓘ Galena Formula: PbS |
| ⓘ Goethite Formula: Fe3+O(OH) |
| ⓘ Hematite Formula: Fe2O3 |
| ⓘ Ilmenite Formula: Fe2+TiO3 |
| ⓘ 'Limonite' References: |
| ⓘ Magnetite Formula: Fe2+Fe3+2O4 |
| ⓘ Malachite Formula: Cu2(CO3)(OH)2 |
| ⓘ Native Gold Formula: Au |
| ⓘ Native Platinum ? Formula: Pt |
| ⓘ Native Silver Formula: Ag |
| ⓘ Pyrite Formula: FeS2 |
| ⓘ Pyrrhotite Formula: Fe1-xS References: |
| ⓘ Quartz Formula: SiO2 |
| ⓘ Schorl Formula: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH) |
| ⓘ Sphalerite Formula: ZnS |
| ⓘ Talc Formula: Mg3Si4O10(OH)2 |
| ⓘ Titanite Formula: CaTi(SiO4)O |
| ⓘ Zoisite Formula: (CaCa)(AlAlAl)O[Si2O7][SiO4](OH) |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
| Group 1 - Elements | |||
|---|---|---|---|
| ⓘ | Native Gold | 1.AA.05 | Au |
| ⓘ | Native Silver | 1.AA.05 | Ag |
| ⓘ | Native Platinum ? | 1.AF.10 | Pt |
| Group 2 - Sulphides and Sulfosalts | |||
| ⓘ | Sphalerite | 2.CB.05a | ZnS |
| ⓘ | Chalcopyrite | 2.CB.10a | CuFeS2 |
| ⓘ | Pyrrhotite | 2.CC.10 | Fe1-xS |
| ⓘ | Galena | 2.CD.10 | PbS |
| ⓘ | Pyrite | 2.EB.05a | FeS2 |
| ⓘ | Arsenopyrite | 2.EB.20 | FeAsS |
| Group 4 - Oxides and Hydroxides | |||
| ⓘ | Goethite | 4.00. | Fe3+O(OH) |
| ⓘ | Magnetite | 4.BB.05 | Fe2+Fe3+2O4 |
| ⓘ | Hematite | 4.CB.05 | Fe2O3 |
| ⓘ | Ilmenite | 4.CB.05 | Fe2+TiO3 |
| ⓘ | Quartz | 4.DA.05 | SiO2 |
| Group 5 - Nitrates and Carbonates | |||
| ⓘ | Ankerite | 5.AB.10 | Ca(Fe2+,Mg)(CO3)2 |
| ⓘ | Malachite | 5.BA.10 | Cu2(CO3)(OH)2 |
| Group 9 - Silicates | |||
| ⓘ | Titanite | 9.AG.15 | CaTi(SiO4)O |
| ⓘ | Zoisite | 9.BG.10 | (CaCa)(AlAlAl)O[Si2O7][SiO4](OH) |
| ⓘ | Schorl | 9.CK.05 | NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH) |
| ⓘ | Talc | 9.EC.05 | Mg3Si4O10(OH)2 |
| Unclassified | |||
| ⓘ | 'Chlorite Group' | - | |
| ⓘ | 'Limonite' | - | |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Goethite | Fe3+O(OH) |
| H | ⓘ Malachite | Cu2(CO3)(OH)2 |
| H | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| H | ⓘ Talc | Mg3Si4O10(OH)2 |
| H | ⓘ Zoisite | (CaCa)(AlAlAl)O[Si2O7][SiO4](OH) |
| B | Boron | |
| B | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| C | Carbon | |
| C | ⓘ Ankerite | Ca(Fe2+,Mg)(CO3)2 |
| C | ⓘ Malachite | Cu2(CO3)(OH)2 |
| O | Oxygen | |
| O | ⓘ Ankerite | Ca(Fe2+,Mg)(CO3)2 |
| O | ⓘ Goethite | Fe3+O(OH) |
| O | ⓘ Hematite | Fe2O3 |
| O | ⓘ Ilmenite | Fe2+TiO3 |
| O | ⓘ Magnetite | Fe2+Fe23+O4 |
| O | ⓘ Malachite | Cu2(CO3)(OH)2 |
| O | ⓘ Quartz | SiO2 |
| O | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| O | ⓘ Talc | Mg3Si4O10(OH)2 |
| O | ⓘ Titanite | CaTi(SiO4)O |
| O | ⓘ Zoisite | (CaCa)(AlAlAl)O[Si2O7][SiO4](OH) |
| Na | Sodium | |
| Na | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Mg | Magnesium | |
| Mg | ⓘ Ankerite | Ca(Fe2+,Mg)(CO3)2 |
| Mg | ⓘ Talc | Mg3Si4O10(OH)2 |
| Al | Aluminium | |
| Al | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Al | ⓘ Zoisite | (CaCa)(AlAlAl)O[Si2O7][SiO4](OH) |
| Si | Silicon | |
| Si | ⓘ Quartz | SiO2 |
| Si | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Si | ⓘ Talc | Mg3Si4O10(OH)2 |
| Si | ⓘ Titanite | CaTi(SiO4)O |
| Si | ⓘ Zoisite | (CaCa)(AlAlAl)O[Si2O7][SiO4](OH) |
| S | Sulfur | |
| S | ⓘ Arsenopyrite | FeAsS |
| S | ⓘ Chalcopyrite | CuFeS2 |
| S | ⓘ Galena | PbS |
| S | ⓘ Pyrite | FeS2 |
| S | ⓘ Pyrrhotite | Fe1-xS |
| S | ⓘ Sphalerite | ZnS |
| Ca | Calcium | |
| Ca | ⓘ Ankerite | Ca(Fe2+,Mg)(CO3)2 |
| Ca | ⓘ Titanite | CaTi(SiO4)O |
| Ca | ⓘ Zoisite | (CaCa)(AlAlAl)O[Si2O7][SiO4](OH) |
| Ti | Titanium | |
| Ti | ⓘ Ilmenite | Fe2+TiO3 |
| Ti | ⓘ Titanite | CaTi(SiO4)O |
| Fe | Iron | |
| Fe | ⓘ Ankerite | Ca(Fe2+,Mg)(CO3)2 |
| Fe | ⓘ Arsenopyrite | FeAsS |
| Fe | ⓘ Chalcopyrite | CuFeS2 |
| Fe | ⓘ Goethite | Fe3+O(OH) |
| Fe | ⓘ Hematite | Fe2O3 |
| Fe | ⓘ Ilmenite | Fe2+TiO3 |
| Fe | ⓘ Magnetite | Fe2+Fe23+O4 |
| Fe | ⓘ Pyrite | FeS2 |
| Fe | ⓘ Pyrrhotite | Fe1-xS |
| Fe | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Cu | Copper | |
| Cu | ⓘ Chalcopyrite | CuFeS2 |
| Cu | ⓘ Malachite | Cu2(CO3)(OH)2 |
| Zn | Zinc | |
| Zn | ⓘ Sphalerite | ZnS |
| As | Arsenic | |
| As | ⓘ Arsenopyrite | FeAsS |
| Ag | Silver | |
| Ag | ⓘ Native Silver | Ag |
| Pt | Platinum | |
| Pt | ⓘ Native Platinum | Pt |
| Au | Gold | |
| Au | ⓘ Native Gold | Au |
| Pb | Lead | |
| Pb | ⓘ Galena | PbS |
Other Regions, Features and Areas containing this locality
North AmericaContinent
North America PlateTectonic Plate
- PedmontiaAccretionary Complex
- Piedmontia DomainDomain
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.
Maryland Mine, Potomac, Montgomery County, Maryland, USA