Gatsby Jewellery Ltd has dated this piece to the 1910s.
The sapphire is claw set in yellow gold and surrounded by twelve bright and lively old mine cut diamonds in platinum rubover settings. Sits nice and low to the finger on a slender 18k yellow gold shank. Truly a wondrous ring.

Accompanied by a report from Gemmological Certification Services (GCS) stating the sapphire shows no indication of heating.
Cut – Cushion cut sapphire. Old mine cut diamonds.
Colour – The diamonds are H to I.

Clarity – The sapphire is loupe clean. (The diamonds are SI1 to SI2.)
Carat – The sapphire is 4.22 carat with a total approximate diamond weight of 1.20 carat.
Circa – 1910.
Size – P (UK) or 7.5 (US). Complimentary sizing is available, can go up or down.

Measurements – The sapphire is 10.99 x 9.49mm. The head of the ring is 17.6 x 15.4mm and sits 5.5mm from the finger.
Metal – 18k yellow gold. The diamonds are set in platinum. Tested.
Video - To view a video of this ring recorded in daylight, please copy / paste the following link into your browser: https://vimeo.com/836565532
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