Chinese Musicians

This beautiful piece was just sitting in the middle of the foreshore, when I went mudlarking one day.  Whilst it is clearly the bottom of a bowl or dish, I have no idea what type of ceramic it is, I doubt it is porcelain as it seems too thick. I wonder how old it is? The pictures look hand painted, but I am completely out of my depth here and my internet searching hasn’t thrown any light on this find.

Bowl Base found Mudlarking on the Thames, London