If you break down the process of producing a kettle into precise detail, it can easily involve more than 100 individual steps and is an undertaking that requires time and patience.
The two kettles seen here are different shapes, but the one on the left also shows the kettle before it has been oxidized and the one on the right has been finished with oxidization. The special characteristic of wazuku iron is that once the surface is coated with an oxidization layer, the internal body of the iron can last an extremely long time without rusting.