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

6.56 g
approximately 4.48 x 4.51 x 2.81 mm central diamonds
14 x 17 mm at widest points
32 mm overall length
Very good antique condition. On reverse, tiny splits to silver mounts around the rose-cut diamonds, barely visible.
Gillers Antiques Ltd has dated this piece to the Edwardian era.
You can view the stock and full dealer information on the Gillers Antiques Ltd Profile Page