Head of pin is molded brass to allow prongs to hold central cabochon. It is open on the back to allow light through. Eight cups with prongs hold clear rhinestones. The central cabochon is unusual, likely crackle glass under a clear glass layer. It sparkles green and pink flashes in a light amber glass, an attempt to imitate yellow topaz or opal. The pin stem has several turns to hold it more securely in fabric. Pin stem is quite thick. Pin is 2 3/16" long--Head is 7/16" diameter.