Learning from the past: Rare ε-Fe2O3 in the ancient black-glazed Jian (Tenmoku) wares

Catherine Dejoie (1) , Philippe Sciau (2) , Weidong Li (3) , Laure Noé (2) , Apurva Mehta (4) , Kai Chen (4) , Hongjie Luo (5) , Martin Kunz (4) , Nobumichi Tamura (6) , Zhi Liu (4)

1 Laboratory of Crystallography [ETH Zürich]
2 CEMES - Centre d'élaboration de matériaux et d'études structurales
3 Shanghai Institute of Ceramics
4 SSRL SLAC - Stanford Synchrotron Radiation Lightsource
5 Shanghai University
6 NAOJ - National Astronomical Observatory of Japan

Ancient Jian wares are famous for their lustrous black glaze that exhibits unique colored patterns. Some striking examples include the brownish colored "Hare's Fur" (HF) strips and the silvery "Oil Spot" (OS) patterns. Herein, we investigated the glaze surface of HF and OS samples using a variety of characterization methods. Contrary to the commonly accepted theory, we identified the presence of ε-Fe2O3, a rare metastable polymorph of Fe2O3 with unique magnetic properties, in both HF and OS samples. We found that surface crystals of OS samples are up to several micrometers in size and exclusively made of ε-Fe2O3. Interestingly, these ε-Fe 2O3 crystals on the OS sample surface are organized in a periodic two dimensional fashion. These results shed new lights on the actual mechanisms and kinetics of polymorphous transitions of Fe2O 3. Deciphering technologies behind the fabrication of ancient Jian wares can thus potentially help researchers improve the ε-Fe 2O3 synthesis.

Domaines: Physique [physics]

Catherine Dejoie, Philippe Sciau, Weidong Li, Laure Noé, Apurva Mehta, et al.. Learning from the past: Rare ε-Fe2O3 in the ancient black-glazed Jian (Tenmoku) wares. Scientific Reports, 2014, 4 (1), ⟨10.1038/srep04941⟩. ⟨hal-01760146⟩