O'Neil Mine (Nail Mine), Lake Mombasha, Town of Monroe, Orange Co., New York, USA
|Latitude & Longitude (WGS84):||41° 17' North , 74° 11' West|
|Latitude & Longitude (decimal):||41.28333,-74.18333|
An iron mine in magnetite ore located about 3 miles SE of Monroe and just North of Lake Mombasha. Closed 1880. Workings featured a pit 50 feet deep by 600 feet long (NE - SW) or up to 1,500 feet long by closing (NYS Museum Bull.).
22 valid minerals. 1 erroneous literature entry.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
1000 - 1600 Ma
Age: Mesoproterozoic (1000 - 1600 Ma)
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052. 
- New York State Museum Bull. Nos. 249-250 (Sep-Oct 1921), Magnetic Iron Deposits of SE NY, Clarke, John M.: Index Map, 45 & 109-110
- Geol. Survey of the State of New York, Geology of Orange Co., Roes, Heinrich (1895): 451-452
- Rocks & Minerals: 20:468.