Qin Ban-liang (bronze currency of the Qin Dynasty), 221-207 BC, and coin mold fragment. The shape of the coin was adopted until the early 20th century. "Qianfan" refers to the mould for the casting of "banliang" coins.
A puzzle box (also called a secret, or trick box) is a box that can only be opened through some obscure or complicated series of manipulations. Description from imgarcade.com. I searched for this on bing.com/images