It was listed by Corvidae Antique. Sold pieces stay on Sellingantiques as a record of what has passed through, and the next one is rarely far away.
Corvidae Antique has dated this piece to the 1960s.

Marked STERLING 925S NORWAY.
In excellent vintage condition. The enamel is undamaged and the hinge and clasp are in good working order.
Size: Approximately 7 x 6cm and 2cm deep.
Weight: 16.4g.
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Corvidae Antique has dated this piece to the 1960s.
Hand picked jewellery from a friendly family business
You can view the stock and full dealer information on the Corvidae Antique Profile Page