This is a copper-based metal intended to imitate gold.
The pendant's surround is composed of 2 snakes head to tail.
The central motif is a floral composition in micro mosaic of glass encrusted in a base
also in black glass imitating onyx (dimensions: H. 25 mm - width 30 mm)
Please note: small chip on the back of the black glass part - see 2nd photo of the back medallion