Gatsby Jewellery Ltd has dated this piece to the 1940s.
The stone is set in a twelve claw coronet collet with ten (five each side) eight-cut diamonds set in the shoulders of the slender 18k yellow gold shank.

Accompanied by a sapphire report from The Gem & Pearl Laboratory stating the sapphire shows no evidence of heating.
Cut:? Oval cut sapphire and eight-cut diamonds.
Colour:? The diamonds are E to F.
Clarity:? There are some visible inclusions in the sapphire. The diamonds are VS1 to VS2.

Carat:? The sapphire is 6.43 carat with approximately 0.05 carat of diamonds.
Circa:? 1940.
Size:? K 1/2 (UK) or 5 3/8 (US). Free sizing available.
Measurements:? The sapphire is 12.0 x 9.5mm and sits 6.1mm from the finger.
Weight:? 3.49 grams.
Metal:? 18k yellow gold. Tested with a Niton DXL Precious Metal Analyzer.
Item # 8121112S092
Gatsby Jewellery Ltd has dated this piece to the 1940s.
Gatsby jewellery are a husband and wife team who have years of knowledge and experience in dealing in fine antique jewellery.
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