"Old Art Nouveau Diamond Ring, Netherlands, Early 20th Century."
A gold and platinum ring set with an antique brilliant-cut diamond weighing approx. 0.28 ct. (SI purity and IJ color), surrounded by a row of old rose cut diamonds set in platinum. Very good condition. Hallmarks: Dutch fineness of 585 gold and 900 platinum. Ring size: 22 (62) 19.75 mm / 62 mm. Weight: 2.74 grams. 
Le Magazine de PROANTIC
TRÉSORS Magazine
Rivista Artiquariato