The big iron coins of Kai Yuan Tong Bao of Min State were produced in several different types .
闽开元通宝大铁钱，存在不同的版别，它们是否均为五代闽国钱？
The Mould-Cast techniques of Yong Long Tong Bao coin of Min state
闽国永隆通宝钱范的制作工艺
Bao State