Malachite occurs with zinc and lead minerals in the SW sec. Malachite occurs sporadically throughout the mines of the Upper Mississippi Valley zinc-lead district. It is commonly as thin crusts associated with other copper minerals. Malachite occurs in the SE NW sec. 36 T. 2N. R.3E. near Gratiot.
Malachite occurs in the Dresser Trap Rock Quarry, sec.
With chalcopyrite and chalcocite in Prairie du Chien Group dolostones found as float blocks in a wash in NE sec. T.10N. R.1E., about 5 km. It occurs as coatings and masses. The masses may be vuggy with botryoidal, fibrous or drusy malachite associated with azurite and other rare copper minerals. Interesting coiled, ringed or helical growths may occur.