Vintage blue enamel flower pin with aurora rhinestones

Lovely large unsigned vintage enamel flower pin. Heavy gold tone plate backing, and accents. Heavily enameled with a pretty two tone light blue enameling. Petals and leaves are set with pale blue crystal faceted rhinestones with a center blue aurora borealis rhinestone. Measures over 2 1/2" in diameter. Pristine condition, and is quality made. Unfortunately there is no makers mark that I can detect. A LOVELY brooch!