AgAu Jewellery has dated this piece to the 1950s.

Metal: 9ct yellow gold.
Stone(s): 1 x Russian Diopside (1ct), 6 x Peridot (0.05ct) totalling (0.30ct), 6 x Opal
Measurements: Ring face 11mm x 11mm
Hallmark: Marked for 9ct
Size. UK Size L1/2
Weight: 2.3g
Condition: Very good condition
AgAu Jewellery has dated this piece to the 1950s.
Agau jewellery offer an extensive range of 9ct and 18ct gold jewellery.
You can view the stock and full dealer information on the AgAu Jewellery Profile Page