Tsubame Tsuiki Doki

Raised by the hammer

Tsuiki means to raise by hammering. A single flat sheet of copper is hammered again and again into a three-dimensional form, and makers can even hammer out the spout of a kettle from the same sheet. The colour shifts with the light, and the lustre deepens the more it is used. It is made in Tsubame in Niigata, a city also famous for Western-style tableware.

Hammer, anneal, repeat

• The sheet is hooked over an iron stake called ategane and hammered, drawn from a dish into a tube and then a rounded bag shape. There are several hundred kinds of stake.
• Copper hardens as it is hammered, so it is softened in a furnace and then hammered again, over and over.
• The surface is decorated by chasing or given an even pattern of hammer marks.
• Finally the piece is boiled in a solution of verdigris and copper sulphate to colour it.

A traveller from Sendai

Copperware in Tsubame is said to have begun in the mid-Edo period, when an itinerant craftsman from Sendai passed on the technique. Kettles were made from copper mined on nearby Mt Yahiko. After the Meiji Restoration, exchange with other areas brought chasing skills and the craft became fine art, laying the base for Tsubame's whole metalworking industry.