Coro door knocker retailer brooch book piece!

Coro door knocker brooch bookpiece with gemstones in gorgeous condition. Its actually a miniature door knocker signed in script Coro. The design is art nouveau with leaves and turquoise stones, rhinestones, and a garnet colored cab in gold plate vermeil. Featured retailer in Marcia Browns book on Coro jewelry. All stones intact, plating in very good vtg condition. Thank you