This specimen is actually quite attractive for this augite varietal that has some aesthetics of geometry to it. It is sharply doubly-terminated, and not cracked and pasty as these tend to get. Jeffersonite is a zincian manganoan variety of augite, a clinopyroxene. Originally described from Passaic Pit (Marshall Mine; Passaic Mine), Sterling Hill, Ogdensburg, Franklin Mining District, Sussex Co., New Jersey. Ex. George Elling Collection.