A Study on the Microstructure and Corrosion Characteristics of Early Iron Age Bronze Mirrors Excavated from the Korean Peninsula

Bronze mirrors, considered important grave goods, were widely used before glass mirrors in ancient times. Most excavated bronze artifacts are covered with corrosive materials and lose their original colors. More importantly, identifying corrosion characteristics and the manufacturing techniques used...

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Bibliographic Details
Main Authors: Nam Chul Cho, Min Kyeong Jang, Il Kwon Huh
Format: Article
Language:English
Published: MDPI AG 2021-03-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/11/5/2441
Description
Summary:Bronze mirrors, considered important grave goods, were widely used before glass mirrors in ancient times. Most excavated bronze artifacts are covered with corrosive materials and lose their original colors. More importantly, identifying corrosion characteristics and the manufacturing techniques used for these artifacts are essential for proper artifact preservation. In this study, Early Iron Age bronze mirrors excavated from the Korean Peninsula were examined to determine their microstructures, corrosion characteristics, and production techniques using various analytical methods, such as Micro-Raman spectroscopy and field emission electron probe microanalysis. As a result, sulfides containing iron suggested chalcopyrite use during production or that the sulfides originated from copper, iron, and sulfur residual matte. The analysis also detected corrosion layers with high tin oxide (SnO<sub>2</sub>) levels and selective corrosion in the α+δ eutectoid phase on the artifact’s surface. In the corrosive layer, cuprite, malachite, and cassiterite corrosion products were detected, and nanocrystalline SnO<sub>2</sub> was identified as a characteristic of long-term soil erosion. Identifying these artifacts’ corrosion characteristics and manufacturing techniques is essential and can greatly contribute to proper artifact preservation.
ISSN:2076-3417