Art Deco brooch in blue chalcedony with marcasites. Heavenly, translucent blue chalcedony is framed by three horizontal bars of bright marcasites in an open-worked pattern. Marked 935 for a higher silver content than sterling, this treasure is probably German. The safety clasp works perfectly. The brooch measures 1-7/8" by 5/8". One marcasite is slightly damaged, only seen with a loupe.