Probably Flemish, late 17th century

dot enamelling on the edge of the bezel, scroll shoulders

Overall condition good with some wear around the collets. The shoulders are engraved with foliat scrolls which were formally enamelled. Traces of black are still visible.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

Similar rings are in the British Museum , the Musée des Arts Decoratifs in Paris and the Provincial Musea Antwerp which suggests a Flemish origin. The present example is unusual in that it incorporates two different stones. 

RELATED LITERATURE:
A.B.Chadour, The Louis and Alice Kock Collection : Rings, Leeds, 1994, Vol I nos.79-782