Beating gold. Also called tanzō 緞造, uchimono 打物, tsuikin 鎚金 and kaji 鍛冶. A basic metalwork technique for hammering out a metal lump with a metal or wooden hammer, beating a metal sheet thin from the front and back, or pressing metal to give it form. Used since the Japanese first started to use metals in the Yayoi period, and employed at first for gold, silver, and copper, then for bronze, nickel, brass, iron, and tin.
Tankin techniques are divided into categories of tsuikin, bankin 板金 and oshidashi 押出. Tsuikin (hammer relief) is beating sheet metal from the front and back to give three dimensional form or relief patterns. In the Kofun period, it was used on long swords and harnesses; it is common on Buddhist altar fittings since the Nara period; in the Muromachi period it is seen on fittings of helmets and armor; and in the Meiji period Yamada Sōbi 山田宗美 utilized it for sculpture.
Bankin (sheet metal process) is the folding and soldering of metal sheets to create three-dimensional forms such as reliquaries, sutra boxes and hanging lanterns.
Oshidashi (extrusion) uses a thin metal sheet on a template and is beaten from the top to transfer the shape; it can be utilized for mass production. In the Nara period, it was used widely for *oshidashibutsu 押出仏 (extruded Buddhist image) and the *sentaibutsu 千体仏 (thousand Buddhist images) inside the *Tamamushi no zushi 玉虫厨子 in Hōryūji 法隆寺. It requires a kanatoko 鉄床 (anvil), *kanazuchi 金槌 (iron hammer), *kizuchi 木槌 (a mallet), ategane 当金 (dolly), *tagane 鏨 (graver), and *yasuri 鑢 (file) to make *butsuzō 仏像 (Buddhist image), butsugu 仏具 (altar fittings), dora 銅鑼 (gongs), bugu 武具 (armory), *kōro 香炉 (an incense burner), pots, dishes, and kettles.