I just got some gorgeous metallic whites from the PP Christmas sale (the pendant is round too, it just looks off-round in this pic). They are 11 to 15mm or so. I plan to re-set the pendant pearl into a ring, encircled with tiny diamonds and colored stones, probably pink, in either a flowery or halo-ish setting.
So that's what I pictured with your beauties too, rings surrounded with little diamonds and other stones that match the pearl or overtone colors.