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

Wonderful deep and rich purple hue to the gemstone.
13.24 g
5.6 x 2.6 x 1.2 cm
Amethyst approximately 28 ct.
Hallmarked for Birmingham, 1892.
Very good antique condition. Small ding along the border on reverse; one of the ball decorations is pierced; part of the applied rope decoration is lacking in one place; tiny fleabites to stone; tiny split along the decorative pierced border.
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