据史载,两宋时期铜钱、铁钱并行,由于铁钱铸量很大,为了防止铜铁钱相互混淆,当局有意将两种钱造成一些区别。在形制上,铁钱显得厚重,穿孔一般也大于铜钱;在文字风格上,则采用与铜钱不同的书体,书写一般粗犷有力。笔者收藏的这枚北宋“绍圣元宝”行书大铁钱(见图), According to historical records, both the copper and iron coins in the Song Dynasty were in parallel. Due to the large amount of iron coins cast, the authorities intended to make some differences between the two kinds of money in order to prevent confusion between copper and iron. In terms of form, the iron money appears to be heavy, and the perforation is generally larger than the copper coin; in writing style, the book body is different from the copper coin, and the writing is generally rough and powerful. This collection of the Northern Song Dynasty “Shaosheng ingot ” line book big iron (see photo),