I have spent hours trying to determine the source of this incredible pendant, to no avail. The initials on the front are some permutation of C S I. The back portrays a classical scene, which is echoed by the laurel wreath surrounding the medallion. There are two figures, one seated in robes and wearing a wreath, the other smaller figure standing and holding a hammer. A lamp of knowledge rests on the pillar behind them. Comes on a chain.