Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
Masses of native copper to several hundred pounds retrieved in recent years (exhibited at the Sterling Hill Mining Museum, Ogdensburg, NJ). 96 pound specimen in Rutgers Museum
Most of the copper occurs not in the basalt but in a zone of darkened, hydrothermally altered mudrock, about 18 inches thick,immediately beneath the basal contact of the basalt.
Chimney Rock Quarry, Bridgewater Township, Somerset County, New Jersey, USA