Gatsby Jewellery Ltd has dated this piece to the 1950s.

Accompanied by a Natural Diamond Identification Report from HRD Antwerp (#210000182414).
Cut – Old European cut.
Colour – K.
Clarity – VVS2.
Carat – 0.87.
Circa – 1950.
Size – L 1/2 (UK) or 5 7/8 (US). Complimentary sizing is available, can go up or down.
Measurements – The centre stone is 6.36 x 6.54mm and sits 6.4mm from the finger.
Metal – 18k white gold. The diamond is set in platinum. Tested.
Gatsby Jewellery Ltd has dated this piece to the 1950s.
Gatsby jewellery are a husband and wife team who have years of knowledge and experience in dealing in fine antique jewellery.
You can view the stock and full dealer information on the Gatsby Jewellery Ltd Profile Page