A number of weights like this one survive from the late antique period. Weights were calibrated to specific standardized measurements. They were hung from hooks on one end of a balance to counter whatever goods were weighed on the other side. Bronze weights in the forms of courtly and mythological women are fairly common. The survival of classical subjects, such as Athena here, shows the pervasive taste for antiquity well into the early Byzantine period.
[ John J. Klejman, New York (sold 1959)]
Franken, Norbert. "Aequipondia: Figürliche Laufgewichte römischer und frühbyzantinischer Schnellwaagen." PhD diss., Verlag und Datenbank für Geisteswissenschaften, 1994. no. CB9, p. 183, pl. 104.