An Interdisciplinary Study of the Provenance of Copper and Lead Raw Materials and the Start date of Use in Japan

2021 Fiscal Year Final Research Report

• Project/Area Number: 17K03224
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Archaeology
• Research Institution: Kurashiki Sakuyo University (2017, 2021); Sakuyo Junior College (2018-2020)
• Principal Investigator: SAWADA Hidemi くらしき作陽大学, 音楽学部, 准教授 (40264577)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: 国産銅鉛原材料 / 古墳時代後期 / 環頭大刀 / 耳環 / 銅鋺 / 鉛同位体比分析 / 蛍光Ｘ線分析 / 学際的研究

Outline of Final Research Achievements

This study attempts to identify the locations producing lead and copper domestically and the date starting to use them in Japan. The copper products from 6th century to 7th century were examined thoroughly through lead isotope ratio analysis, X-ray fluorescence analysis and metallographic analysis based on archaeological knowledge.The objects such as Kan-toh-tsuka-gashira, Jikan, horse tack and copper bowls were studied. Surveying materials helped to identify the locations where lead and copper were produced: the mines in the Izumo and in the area of Sakurago and Naganobori. According to the period to which the materials helping to determine the mines were attributed, the use of domestic lead and copper was started at the end of 6th century. Additionally, it was assumed that foreign settlers were involved in developing these mines. It was also inferred that there was a supply of raw materials from Silla in the latter half of 6th century prior to using domestic raw materials.

Free Research Field

日本考古学

Academic Significance and Societal Importance of the Research Achievements

本研究では、６世紀後半から７世紀代の銅製品の理化学的分析によって国産銅鉛原材料の使用開始時期を追究したが、特に蛍光Ｘ線分析では、定性分析とはいえ悉皆的な調査によって合金成分の傾向性を見いだし、その類型が考古学的観察成果と整合した。また対象資料の編年的位置づけと、その時系列に沿った鉛同位体比分析の遂行によって、原材料産出地の推移が判明したことは、学術成果とともに新たな学際的研究手法の完成でもあった。