Despite the fact these fabulous birds seem very familiar, I haven't had much luck finding any specific information on them.  My best guess is that the unsigned trio is made of sterling, and probably designed by Coro /Corocraft in the 1930's or 1940s.  All of the brooches are equipped with c-clasp closures, and feature clear rhinestone accents on their metallic and opaque blue enamel bodies.  Sizes include: 2-3/4" x 7/8" (largest); 2-1/4" x 3/4" (middle); and 1-3/4" x 5/8" (smallest).  Superb quality, excellent condition.  WAS $120.00 - NOW $110.00