Corvidae Antique has dated this piece to the Edwardian era.
The shank is stamped 9CT and inscribed in beautiful script: "March 11th 1912 From Mother to Evelyn." The ring of course may be slightly older.

Size O and a half (UK) 7.5 (US). The cameo measures 1 x 1.2cm.
Weight: 2.5g.
Corvidae Antique has dated this piece to the Edwardian era.
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