Gatsby Jewellery Ltd has dated this piece to the 1940s.
On a slender 18k white gold shank.

Accompanied by a Diamond Report from IGI (#457059604).
Cut – Old European cut.
Colour – I.
Clarity – SI2. (The diamond is clean to the naked eye.)
Carat – 1.41.
Circa – 1940.
Size – M 1/2 (UK) or 6.25 (US). Complimentary sizing is available, can be sized up or down.
Measurements – The diamond is 7.07 x 7.26mm and sits 5.7mm from the finger.
Metal – The diamond is set in platinum and the band is 18k white gold. Tested.
Gatsby Jewellery Ltd has dated this piece to the 1940s.
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