Cast iron axes found, along with bronze artifacts, in the site in Hapsong-ri, Buyeo associated with the 2nd Century BC tell us when the Iron Age was started in southern regions of the Korean Peninsula. Tubular-shaped glass objects were also unearthed there. Fire clay was applied to the surface of a metal stick to make it easier to detach the produced glass more easily. Then, glass liquid was poured onto the surface. It turned out to be lead-barium glass as a result of the content analysis. Lead-barium glass objects are mainly found, along with cast iron axes, in the sites associated with the early Iron Age. Thus, it is guessable that glass processing was closely related to the skill of production of iron objects. Glass objects and tubular jade items have been found in many sites located along the Geumgang River, including Hapsong-ri, Buyeo.