Gatsby Jewellery Ltd has dated this piece to the 1910s.
The stone is secured by four claws in a square collet which sits between gorgeously crafted shoulders set with eight (four each side) eight-cut diamonds leading to a hand-engraved platinum shank. Currently UK size L 1/2 or US size 5 7/8 (complimentary sizing available).

Accompanied by a De Beers Institute of Diamonds grading report (#010000277581). A unique number has been inscribed on this diamond providing utmost security.
Cut – Old mine cut in the centre, eight-cuts in the shoulders.

Colour – The centre is K, the diamonds in the shoulders are G to H.
Clarity – The centre is I1 (clean to the naked eye). The diamonds in the shoulders VS1 to VS2.
Carat – The centre is 1.06 carat, with a further approximate 0.13 carat in the shoulders.

Circa – 1910.
Size – L 1/2 (UK) or 5 7/8 (US). Complimentary sizing is available, can be sized up or down.
Measurements – The centre is 6.48 x 6.18mm and sits 5.3mm from the finger.
Weight – 3.27 grams.
Metal – Stamped 5% IRID PLATINUM, indicating the ring is 95% platinum and 5% iridium. Tests as such.
Gatsby Jewellery Ltd has dated this piece to the 1910s.
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