Woodbridge Antiques has dated this piece to the 1960s.
There is a good fastening clasp at the back.

A perfect gift, made by a collectable designer and in fabulous condition.
Period: c. 1966 -`1988
Measurements: Width: 2.8 cm Height: 1.8 cm Weight: 4.2 grams
Weights and measurements are approximate.
NJL35990
Woodbridge Antiques has dated this piece to the 1960s.
Specialists in quality antique silver, fine jewellery & accessories
You can view the stock and full dealer information on the Woodbridge Antiques Profile Page