Such a charming piece!
 
An ouroboros snake with emerald eyes wraps around the central locket, a dendritic agate in a gold pinched collet setting.
The back is engraved: 'My father's gift, July 18th 1829', a gift from father to daughter or son.
 
Shown here in the perfect fitted box but sadly this is a box of my own and did not come with the piece.
 
weighs - 7.14g
measures - 23mm diameter
English 1829
Gold, dendritic agate, emeralds
Excellent condition