Gatsby Jewellery Ltd has dated this piece to the 1930s.

Accompanied by an independent jewellery report from IGR (#30310097).
Cut – Octagonal cabochon emerald and rose cut diamonds.
Colour – The diamonds range from F to G.
Clarity – The diamond are I1 (clean to the naked eye)

Carat – The emerald is approximately 2.31 carat, with a total approximate diamond weight of 0.05 carat.
Circa – 1935.
Size – K (UK) or 5 1/8 (US). Complimentary sizing is available, can be sized up or down.
Measurements – The head of the ring is 12.1 x 12.2mm and sits 7.5mm from the finger.
Metal – 18k white gold. The diamonds and emerald are set in platinum.
Gatsby Jewellery Ltd has dated this piece to the 1930s.
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