Shield-Shaped Mirror
Bronze mirror
The rear mirror appears like a weapon-shield, in a shape rotated 180 degrees. It embodies the three highest virtues of the ruler.
Object ID
Tang_005
Age
Tang Dynasty (618 – 907 AD)
Material
Bronze
Color
Bronze-colored
Length
16.6 cm
Width
11.5 cm
Condition
good
Price
on request
Description
The mirror appearing in a kind of weapon-shield, has a shape rotated 180 degrees. There are artificially casted reliefs which are framed by a relief-like double-edge. The shield is arranged in three parts: the parallel vertical bands with inscriptions, the two swords and the rectangle middle field that has a specific decoration with a kind of stylized tree, may be over a knob or a performance of mountains. The swords have each a knob, a handle and a cross-gard, a cutting and a sharp vertically metal. The originally smooth mirror-side shows metal-layers pilled off on different strength. There is also irregular oxidation and greenspan.
The symbolic meaning is outstanding. Sword, „gem“ and mirror refer to the highest virtues of the ruler: The sword stands for bravery, the „gem“ for the will to act justly and the mirror for the wisdom. The artifact represents also the defense against demons.
For many centuries the question arose again and again how such a magic mirror worked. The recent research of two professors at the Physics Faculty of the University of Münster/ Germany came to a convincing result. They referred to another Prof. Ayrton who explained already in a lecture 1878 the creation techniques of Chinese mirrors. A mirror was produced by pouring molten bronze into a mold that was decorated with a relief-like ornament. The solidified blank then was processed on a wooden base with a kind of plane to smooth the surface.
Through appropriate processing of the surface and the effect of the relief on the back a slightly wavy surface is created. When light falls on it the recesses look like small concave mirrors. As a result, a slight brightness modulation can be seen in the reflected light. Its structure corresponds to the depressions and elevations of the relief on the back. The mirror unfolds its magic when it is exposed to the light of a bright light source – the best is the sun – when projecting onto a wall in shadow. In the bright spot of light you can more or less see the relief embossed on the back.Therefore, those artifacts are also named „magic mirrors“. [1] (HV)
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[1] Schlichting, Hans-Joachim/ Ucke, Christian (checked: 24_06_07): Der chinesische Zauberspiegel. https://www.uni-muenster.de/imperia/md/content/fachbereich_physik/didactic_physik/didactic-physik/publikationen/chinesische Zauberspiegel