This is pair of vintage Mexican sterling silver, screw-back earrings that look much like bat wings or butterfly wings. Signature: one is stamped on the reverse with the eagle assay mark with the number 23, Mexico, and perhaps sterling (this last word is difficult to read). The other is stamped with the same eagle mark and with the AE within a heart shaped M. This mark is likely that of Miguel (Miguel Garcia) Taxco: first master smith at Spratling's workshop and foremost designer at Rancho Alegre (founded 1956) in Taxco. Measurements: almost 1-1/4” high x over 5/8” at the widest. Very good to near excellent vintage condition. The screw-backs work properly.