Sphalerite from selected localities.
USA | |
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| Heyl, A. & Pearre, N (1965) Copper, zinc, lead, iron cobalt and barite deposits of the Piedmont Upland in Maryland: Maryland Geological Survey: Bulletin 28, 72 p. |
| Ostrander, C. W. & W. E. Price (1940) Minerals of Maryland: Natural History Society of Maryland , 92 p. |
| Mines of the Washington D.C Area |
Heyl, A. & Pearre, N (1965) Copper, zinc, lead, iron cobalt and barite deposits of the Piedmont Upland in Maryland: Maryland Geological Survey: Bulletin 28, 72 p. |
Farmers Cooperative Limestone Quarry, New London, Frederick County, Maryland, USA