My Miriam Haskell Mystery post from last November features a bracelet and two brooches that match this necklace design.
Close inspection of the cloisonne dragon beads seems to delmonstrate the work of two different artisans, showing:
1) White and black eyes, five toes, and evenly applied scales
2) Black eyes, four toes, rather sloppy application of the scales
Another post is in the works about the mysterious artisan who put only four toes on his dragons.