Three Antique Jewelled Gold and Enamel Rings in the 'Renaissance Style'

the first centered with a cabochon turquoise with closed-back setting, on a raised quatrefoil mount with opaque black and translucent red enamel strapwork, flanked by chased and enamelled arabesques; the second similarly decorated centering a table-cut diamond and ruby with closed-back settings; the third centered with a natural pearl with closed-back setting, on an openwork foliate mount with traces of translucent green enamel, flanked by enamelled and chased floral and foliate motifs, all apparently unmarked

inner diameter 1/2 in., 1.27 cm

inner diameter 5/8 in., 1.4 cm

inner diameter 3/4 in., 1.9 cm