National Treasures & Important Cultural Properties
of National Institutes for Cultural Heritage, Japan

Bronzeware originally came to Japan from the Korean Peninsula during the Yayoi period as weapons. They later morphed in function and form, becoming longer and wider as people began using them as ritual implements instead. Among such weapons are halberds, which are made by attaching a blade perpendicularly to a shaft. From the mid- to late Yayoi period, the blades of halberds became dull and the tangs where they were attached to the shafts became weaker, suggesting that they had lost their functionality as weapons. Archaeologists have classified the largest, most evolved of these as having a “wide blade,” with blades of other sizes labeled relative to them.

Bronze halberds with wide blades have been unearthed primarily in northern Kyushu, though few in number. Similarly, only a few molds used to create them have turned up around the Fukuoka plains. It goes without saying that complete, undamaged molds are even rarer. This object is one such example, having allegedly been excavated from a hill near Tatara in Higashi Ward, Fukuoka City, during reclamation works in 1952. Made out of quartz-feldspar porphyry, this mold features a carved indentation of a wide halberd blade on its top surface. The reverse side of the mold, as well as its side edges, seem to have been deliberately yet carelessly rounded off, and bear marks from the finishing process. On the other hand, the two thinner ends drop off from the top surface almost vertically, and are rough, with keys to help align the other half of the mold. The casting surface has been polished smooth, and the black-brown markings in the mold cavity are thought to be remnants from the actual casting process. The channels carved in at the tip of the blade and the tail of the tang likely function as a sprue and a gas vent, though it is unclear which is which.

Another mold for casting bronze bracelets, which was discovered near Tatara, has similarly been designated an Important Cultural Property. The presence of these molds suggests that there was likely a bronze forging site nearby that operated during the late Yayoi period.