Mössbauer spectroscopy and neutron activation analysis of ancient Chinese glazes

Abstract The optical spectra of the glaze of Ru porcelain made in the Chinese Northern Song Dynasty (AD 960–1126) were measured by the chromatometer to determine the relations between glaze color and its dominant wavelength ( λ D ). The concentrations of 30 coloring elements in the glaze were determined by neutron activation analysis (NAA). Iron was the dominant coloring element. Mossbauer spectroscopy detected that iron existed in the state of structural Fe 2+ and Fe 3+ ions. A relationship between λ D of various colored glazes and the Fe 2+ /Fe 3+ ratio was established. As the Fe 2+ /Fe 3+ ratio gradually increases, the glaze color of Ru porcelain will gradually change from pea green to sky green. All the Ru porcelains were fired in a reducing atmosphere. The sky green Ru porcelain was fired in the most reducing atmosphere and at the highest temperature, the powder green in a more reducing atmosphere and at a lower temperature and the pea green in a lightly reducing atmosphere and at the lowest temperature.