Gatsby Jewellery Ltd has dated this piece to the 1900s.
The diamond is mounted in a classic six claw collet with an open gallery, leading to knife edged band.

Contemporary hallmarks, London.
Accompanied by an independent jewellery report by IGR (#30310057).
Cut – Old mine cut.
Colour – I.
Clarity – VS2.
Carat – 0.54.
Circa – The diamond is circa 1900, the mount is new.
Size – M (UK) or 6 (US). Complimentary sizing is available, can be sized up or down.
Measurements – The diamond is 4.75mm by 4.8mm and sits 5.3mm from the finger.
Metal – Platinum. Hallmarked.
Gatsby Jewellery Ltd has dated this piece to the 1900s.
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