Large Antique Coat Button Black 1-5/8 inch, Metal Flowers on Celluloid

Nice vintage button from the 1800s. It would be great on a coat or cape. The base of the button appears to be celluloid or another early plastic. Ridged sides with metal ring that has flowers and a small stud. Metal loop on the back with piece of round cardboard ties on the back of it - maybe the button is unused.
The button is in very good condition. The metal ring and flowers are turquoise from patina. The tiny stud has it's finish lightly rusted.