AgAu Jewellery has dated this piece to the 1950s.

Metal: 18ct white gold pendant/ 9ct white gold chain.
Stone(s): 10 x Diamonds (1 point), 1 x Ruby (0.25ct)
Measurements: Pendant/Chain Measurements 17mm x 8mm. Chain 18"/45cm
Hallmark: Pendant Marked 18ct/ Chain Marked for 9ct
Weight: 1.2g
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