Well I think it's ancient. The only ones with big holes that I've seen like that were from around 100 BC to 100 AD. But I'm not very experienced with these.
It is difficult trying to make out the characters but I think it is a tong zhi tong bao (同治通寶) coin cast during the reign (1862-1874) of Emperor Mu Zong of the Qing (Ch'ing) Dynasty. If there were originally any characters on the reverse side identifying the mint, they are no longer legible. Many poor quality coins were produced during that time period. Gary
Gary is quite right! It is an illegally forged Tongzhi Tongbao, a common phenomenon at that time. These unauthorized cashes are much smaller and thiner than official ones, and contain less copper. People at that time always refused to accept these cashes. So they were actually used as half-cash or even smaller denomination. Regards, Assur
Good information Gary and Assur. I could tell from the photo it could not be an official mint issue, due to the shape of the center hole and the fact it was not finished.