Vintage Judith Jack Sterling Marcasite Earrings. Stunning pair of door knocker style earrings. These bold earrings are completely encrusted with square cut marcasite stones. They measure 1.62 inches long by .75 inches wide, are for pierced ears, and have French backs to hold the earrings securely in place. They are marked on the back of each earring, Sterling and JJ logo. These earrings are in excellent condition.