The coro company was a high end costume jewelry company that began in 1901. Heading into the 1940s they started experimenting with different metals like sterling silver. This necklace is gold plate over sterling silver and was made some time in the 1940s. There are two stars of this show. The incredible faceted amber glass prong set navettes and the vintage book chain. This piece feels very Art Deco and was definitely designed in that style.  A true collector's piece that you can pass down one day in the future.
Marked Sterling Coro on back.
Please Note: There is some wear to part of the chain in the back. You do not see this from the front when wearing this piece. 
Length: 13.5 inches including fold over clasp

Vintage 1940s Sterling Coro Amber Glass Book Chain Choker Necklace