Gillers Antiques Ltd has dated this piece to the Victorian era.

This could possibly be a depiction of Athena or Hecate, the two goddesses associated with snakes.
The straight Roman nose portrayed here is indicative of the first half of the 19th century, as later Victorians preferred a more feminine, upturned nose.

The brooch is set in an 18ct yellow gold frame stamped "750"; the frame has a roll-over clasp and an additional security chain. The cameo has been reset at some point, as the frame dates to 20th century.

Made in Italy, c. 1830's (frame later date).
20.02 g
6.6 x 5 x 1.6 cm
Cameo in excellent antique condition. Tiny sliver missing on reverse (hidden underneath the frame); several small dings to the frame on the lower part.
Gillers Antiques Ltd has dated this piece to the Victorian era.
You can view the stock and full dealer information on the Gillers Antiques Ltd Profile Page