This is a jabot pin (hat pin) from the Art Deco period, composed of an unknown plastic. It may be celluloid, or some other type of plastic. The end pieces are molded together and then cut and polished, meaning that the two colors were cast together. One end of the jabot unscrews to allow for attachment to a hat, jacket, or anything you want to fasten it to! Excellent condition, allowing for the darkening of the cream color with age.