This antique open vanity jar or pin dish is a lovely example of the Wavecrest line made by C F Monroe. It dates to the late 1800s. It is a delicate pale green with beautiful raised enamel decoration typical of the Wavecrest pieces. It was designed as an open dresser jar with no lid, so nothing is missing. It is unmarked. The bottom has what might be a partial impressed mark, but I think it's more likely that it was either never marked or the backstamp has worn off over the years.
It is about 3 1/2 inches wide and about 1 1/2 inches tall. It is in excellent condition with only minor wear to the enamel and the expected age wear to the bottom. The brass mount is in very good condition with a little patina. It would polish up nicely if you wanted it shiny.