Mammy Coin Bank

I found this old Mammy coin bank and I cannot find any information about her. She is approximately 5 inches tall (I do not have an official measuremeant). The Mammy has a white apron and scarf over a light blue dress. The coolest part about the bank is the lock on the bottom. The key opens the lock and the lock mechanisms comes completely off of the bank. It amazed me I discovered such an old piece with all 3 pieces still intact. I'd really love to know more about this piece. Time period? Manufacturer? Value? Any information would be much appreciated!