Its definitely copper underneath with brass applied using a lost wax method,..over on this side of the pond...I,ve seen similar things like this...e.g....when apprentice,s were nearing the end of their time they were asked by their journeyman =Teacher,to make something as a reminder of their apprenticeship,..when I was finishing my time I had to make a wooden tool chest..which i still have after 42 years,this looks like something a plumber would have made...or perhaps a budding metal sculptor...and the date on the bottom is probably the date when he made it...