ZHENGZHOU - Chinese archaeologists have found an iron smelting waste dump dating back to the Han Dynasty (202 B.C.-220 A.D.) in Queshan county, Central China's Henan province.

"The dump is a deep ditch, specially renovated to store the waste produced during iron smelting processes," said Zhou Runshan, leader of the excavation team.

Archaeologists have excavated a large number of objects from the waste pile, which is up to 6 meters deep, such as iron chunks, slabs, pottery moulds, slag and other residue.

The dump adjoins an ironworks ruin. Based on the pottery moulds found in the dump, archaeologists believe that the major task of the ruin was manufacturing tools.

The Han Dynasty had a booming iron smelting industry, with hundreds of ironworks ruins from the dynasty being found across China. They were usually built in two places: near a town o ran iron mine.

"This ironworks ruin was outside a town. Perhaps our ancestors had advanced city planning thoughts, trying to reduce the impact of industrial pollution on our towns," Zhou said.

As excavation work advances, Zhou said that they would find more information to better understand the ironworks ruin and its layout, the source of iron ore, the production line, labor division and iron smelting skills.