It was listed by Gatsby Jewellery Ltd. Sold pieces stay on Sellingantiques as a record of what has passed through, and the next one is rarely far away.
Gatsby Jewellery Ltd has dated this piece to the 1870s.

Contemporary hallmarks. London.
Cut – Old mine / miner cut.
Colour – G.
Clarity – VS1.
Carat – 0.52.
Circa – The diamond is circa 1870, the mount in new.
Condition – The metal can be polished to “new” if you prefer.
Size – K 1/2 (UK) or 5 3/8 (US). Complimentary sizing is available, can be sized up or down.
Measurements – The diamond is 5.25mm by 5mm and sits 4.7mm from the finger.
Metal – Platinum. Hallmarked.
Gatsby Jewellery Ltd has dated this piece to the 1870s.
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