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 1950s.

Marked STERLING JTOSTRUP NORWAY.
The hinge and clasp are in good working order.
Size: 6.3 x 3cm.
Weight: 7.0g.
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Corvidae Antique has dated this piece to the 1950s.
Hand picked jewellery from a friendly family business
You can view the stock and full dealer information on the Corvidae Antique Profile Page