摘要
Twenty Yongzheng copper coins were fast dating by X-ray energy dispersive spectrometer with scanning electron microscope(SEM-EDS)according to official ingredient.The 20 coins were classified in two groups according to the results.Group 1 represents the coins minted before AD 1728 and group 2 represents the coins minted after AD 1728.At concentration range(0.00%–5.13%),the distribution of lead is not homogeneous in the coins,and the largest diameter of lead inclusion is less than 15μm.The official fineness degrade is supported.
基金
Supported by the Project of Instrument Upgraded of Ministry of Science and Technology of China