Edwardian lavalier necklace in sterling and marcasite

The epitome of finery! The pendant, which is crafted on three levels (easily seen in the last picture, of the back) has the fine geometric and floral designs typical of the period, about a century ago. The marcasites pick up light nicely. It is about two inches long, while the chain is about 16-1/2 inches counting both sides. Stamped Sterling on the back of the pendant. I see no markings on the chain. In very good condition, with some patina.