Millington Quarry (Morris County Crushed Stone Co. Quarry; Tilcon Quarry), Bernards Township, Somerset Co., New Jersey, USA
|Latitude & Longitude (WGS84):||40° 40' North , 74° 31' West|
|Latitude & Longitude (decimal):||40.66667,-74.51667|
Amygdaloidal cavities in the Hook Mountain (Third Watchung) basalt. Quarrying began in 1895, and continued on and off, until the early 1970's. After a period of inactivity, the quarry restarted in 1979. The quarry was mined aggressively producing over 1 million tons/year in many years. From the middle of the 1980's, until early 2007, mineral specimens were found in abundance. The mineralized zone has now been removed, and the pit is currently being refilled with trucked in rock and dirt, for a future housing development.
The Millington Quarry was, scientifically, one of the most interesting of the basalt quarries in the region. Cummings (1985) described how mineral deposition was zoned vertically within amygdaloidal horizons. Subsequent to this publication it became apparent that secondary minerals at Millington (and also at the Chimney Rock Quarry) also exhibited other distinct distribution patterns (Cummings, 1988, 1998) These patterns were directly related to the varying porosity, hydraulic conductivity and glass content of the basalt and the distance of the deposition site from the fluid source in the sediments. They provided strong evidence that mineral deposition did not occur in a stagnant, burial metamorphic environment but resulted from actively circulating fluids moving upward, out of the sediments and through the basalts.
40 valid minerals.
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
174.1 - 201.3 Ma
Age: Early Jurassic (174.1 - 201.3 Ma)
Stratigraphic Name: Towaco Formation
Description: (Olsen, 1980) - Reddish-brown to brownish-purple, fine- to medium-grained micaceous sandstone, siltstone, and silty mudstone in upward-fining sequences 1 to 3 m (3-10 ft) thick. Distributed throughout formation are eight or more sequences of gray to greenish- or brownish-gray, fine-grained sandstone, siltstone and calcareous siltstone and black, microlaminated calcareous siltstone and mudstone containing diagnostic pollen, fish and dinosaur tracks. Sandstone is commonly trough cross laminated; siltstone is commonly planar laminated or bioturbated, but can be indistinctly laminated to massive. Thermally metamorphosed into hornfels where in contact with Hook Mountain Basalt. Conglomerate and conglomeratic sandstone with subrounded quartzite and quartz clasts in matrix of light-red sand to brownish-red silt (Jtc) interfingers with rocks of the Towaco Formation north and west of New Vernon. Maximum thickness is about 380 m (1,250 ft).
Comments: Newark Supergroup, Brunswick Group (Lyttle and Epstein, 1987). Units Jt and Jtc are described together on printed map. The units were split into separate records and appropriate descriptions for each were used.
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. 
Manchester, J.G. (1931) The Minerals of New York City and Its Environs. New York Mineralogical Club Bulletin: 3-81.
Cummings, W. (1985) Mineralization at the Millington Quarry, New Jersey. Rocks & Minerals: 60: 213-218.
Cummings, W. L. (1988), The Role of Sedimentary Connate Brines in the Mineralization of the Watchung Basalts- In Husch, J.M. and Hozik, M.J., Eds., Geology of the Central Newark Basin, Field Guide and Proceedings, Geological Association of New Jersey, fifth Annual Meeting: 135–147.
Tschernich, R. (1992) Zeolites of the World, 67 p.
Becker, M. (1998) Recent Mineral Finds at the Millington Quarry, Somerset County, New Jersey. Rocks & Minerals: 73: 320-324.
Cummings, W. L. (1998), Geology of the Chimney Rock Copper Occurrence, A Deposit Typical of the Watchung Basalts- In Puffer, J.H. Ed., The Economic Geology of Central New Jersey, Field Guide and Proceedings, Geological Association of New Jersey, fifteenth Annual Meeting: 29–49.
Cummings, W. (1999) Letters to the Editor, Millington Quarry. Rocks & Minerals: 74-149.
Kent, B.P. and Butkowski, B. (2000) Minerals of the Millington Quarry, Somerset County, New Jersey. Mineralogical Record: 31: 399-411.
Maertens, J. (2007) Collecting Minerals at Tilcon's Millington Quarry. The Tilcon Times, Summer: 9-10: 26.
Wilson, W. (2007) Millington New Jersey. Mineralogical Record: 38: 230-232.