Mineral Evolution Database

Created and maintained by the Mineral Evolution Project in partnership with RRUFF and mindat.

Mineral locality data provided by mindat.org

The Mineral Evolution database is currently under development.

The goal of this page is to present localities at which the mineral is found, and estimates of the oldest possible geologic age of the minerals at these localities.

Locality Name:
Potomac, Montgomery Co., Maryland, USA

mindat Locality ID: 253478
mindat URL: http://www.mindat.org/loc-253478.html

Tectonic Settings:

Total number of sublocalities beneath "Potomac, Montgomery Co., Maryland, USA": 6
Total number of bottom-level sublocalities: 6

Number of Child Localities: 6
Child Localities:
Eagle Mine
Ford Mine
Maryland Mine (Allen Shaft)
Montgomery Mine (Potomac Mine)
Stanmore Drive
Watson Mine (Anderson Property; Potomac And Watson Mine)

Latitude: 39°2'12"N
Longitude: 77°13'47"W
Decimal Degree (lat, lon): 39.036666666667,-77.229722222222

A	This mineral is Anthropogenic.
G	This mineral is directly dated.
B	This mineral is reported as having this age.
Y	This mineral is using an age reported as an element mineralization period.
O	This mineral is using an age calculated from all data at the locality.
R	The age displayed for this mineral originates from a different, non-child locality.
P	The age displayed for this mineral is the range of ages for this mineral at all of this locality's children.
	This mineral's age has not yet been recorded.

Arsenopyrite	Chalcopyrite	Clay	Copper	Corundum	Diaspore	Epidote	Malachite	Mica	Nickeline
None	Pyrite	Quartz	Rocksalt	Sphalerite	Spinel	Talc	Tetradymite	Titanite	Tourmaline

Ankerite ()*	Arsenopyrite ()*	Chalcopyrite ()*	Galena ()*	Goethite ()*
Gold ()*	Ilmenite ()*	Magnetite ()*	Malachite ()*	Muscovite ()*
Pyrite ()*	Pyrrhotite ()*	Quartz ()*	Schorl ()*	Silver ()*
Sphalerite ()*	Talc ()*	Tetradymite ()*	Titanite ()*	Zoisite ()*

This Mineral list contains entries from this locality, including sub-localities. Minerals in bold are reported by mindat.org as occurring directly at this locality, and do not occur at any children (sublocalities) of this locality.

Elements at this locality, including sub-localities: Ag Al As Au B Bi C Ca Cu Fe H K Mg Na O Pb S Si Te Ti Zn

Elements from minerals reported directly at this locality:

Structural Groups for minerals in this locality:
Arsenopyrite Chalcopyrite Clay Copper Corundum Diaspore Epidote Malachite Mica Nickeline
None Pyrite Quartz Rocksalt Sphalerite Spinel Talc Tetradymite Titanite Tourmaline

20 IMA Minerals at location:

Mineral name	Structural Groups	IMA Formula	# of Sublocalities containing mineral	LOCALITY IDs, not mindat ids	# of localities containing mineral
Ankerite ()*	None	Ca(Fe²⁺,Mg)(CO₃)₂	1	218950	3092
Arsenopyrite ()*	Arsenopyrite	FeAsS	1	218950	9052
Chalcopyrite ()*	Chalcopyrite	CuFeS₂	1	218950	27198
Galena ()*	Rocksalt	PbS	2	218950,218951	24243
Goethite ()*	Diaspore	FeO(OH)	2	218950,218952	7437
Gold ()*	Copper	Au	5	218948,218949,218950,218951,218953	30554
Ilmenite ()*	Corundum	Fe²⁺Ti⁴⁺O₃	1	218950	5433
Magnetite ()*	Spinel	Fe²⁺Fe³⁺₂O₄	2	218949,218950	14899
Malachite ()*	Malachite	Cu₂(CO₃)(OH)₂	1	218950	12537
Muscovite ()*	Mica Clay	KAl₂(Si₃Al)O₁₀(OH)₂	1	218951	17380
Pyrite ()*	Pyrite	FeS₂	5	218949,218950,218951,218952,218953	39462
Pyrrhotite ()*	Nickeline	Fe₇S₈	1	218950	9056
Quartz ()*	Quartz	SiO₂	5	218949,218950,218951,218952,218953	61156
Schorl ()*	Tourmaline	NaFe²⁺₃Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)	1	218950	2705
Silver ()*	Copper	Ag	1	218950	5186
Sphalerite ()*	Sphalerite	ZnS	1	218950	21482
Talc ()*	Clay Talc	Mg₃Si₄O₁₀(OH)₂	1	218950	3337
Tetradymite ()*	Tetradymite	Bi₂Te₂S	1	218949	510
Titanite ()*	Titanite	CaTi(SiO₄)O	1	218950	4899
Zoisite ()*	Epidote	Ca₂Al₃[Si₂O₇][SiO₄]O(OH)	1	218950	1025

No ages have been assigned to this locality yet.

Sample	Source Locality	Reference URL

All locality data graciously provided by mindat.org

All age data...