These brooches with the hooks on back were used to catch the guard chains ladies wore in the late 1800s. A watch or some pendant could be on the long guard chain (around 54 inches) and these brooches were used used to catch some of the length. Victorians did like their jewelry! I always pick these up when I see them. This one is gold but the back is base metal and has a ring closure. The design of the hearts or clover leaves holds three small emeralds. Just over one inch wide.