These earrings are a variation of the disk and pendant type that began in the sixth century B.C. and enjoyed popularity throughout the Greek world during the Hellenistic period. Here the disk has been modified into a pediment shape, and the pendants are in the form of female heads.
Richter, Gisela M. A. 1924. "Greek and Roman Jewelry: Recent Accessions." Bulletin of the Metropolitan Museum of Art, 19 (2): p. 35.
Alexander, Christine. 1928. Jewelry: The Art of the Goldsmith in Classical Times as Illustrated in the Museum Collection. p. 32, fig. 68, New York: The Metropolitan Museum of Art.
Richter, Gisela M. A. 1953. Handbook of the Greek Collection. p. 157, Cambridge, Mass.: Harvard University Press.