Although unmarked, this dress clip/brooch combination is similar to the Coro Duet or Trifari Clipmate.  The clip is from an estate sale and is marked Pat. No. 2044225, dating it to 1936. It has a beautiful and distinctive design of flower-like swirls covered in clear pavé rhinestones set in rhodium.  It is in very good condition with one rhinestone replacement.  It's hinge has been repaired.  I'm so happy to have this clip with it's original connecting hardware piece so you may enjoy it as either a brooch or dress clip.  It measures 2 3/4" wide by 1" tall.

 

Clips apart:

 

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