Greenstone Quarry, GAF Ruberoid Mill, Blue Ridge Summit, Adams Co., Pennsylvania, USA
|Latitude & Longitude (WGS84):||39° 44' 50'' North , 77° 27' 19'' West|
|Latitude & Longitude (decimal):||39.74722,-77.45528|
In 1923 the Funkhouser Company of Hagerstown acquired the operation and started to supply natural greenstone for roofing shingles. The Ruberoid Corp acquired the plant in 1959 and GAF Corp assumed control in 1967.
Native copper occurs in quartz veins and epidote-rhyolite host rock. Secondary copper mineralization is present. Epidote-rhyolite is quarried for use as an aggregate in the production of roofing shingles. The operation currently includes 625 acres housing quarries, mills and color processing units.
6 valid minerals.
Rock Types Recorded
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Entries shown in red are rocks recorded for this region.
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
541 - 4000 Ma
Age: Precambrian (541 - 4000 Ma)
Description: Dark-gray, fine-grained intrusives; locally, mineralogy is altered and unit has greenish color.
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.