Black, heavy, made to last a lifetime. Oshu in Iwate is the home of Nanbu ironware, known above all for iron kettles. Nanbu ironware is plain, black and substantial, but the more you use it the more character it takes on; it is handed down for decades, sometimes across three generations. Boil water in an iron kettle and the water grows mellow, with iron in it too, utility and beauty both. The making is dizzying: a mold is built from sand and clay, and molten iron poured in. The fine dots on the surface, the "hailstone pattern," are pressed one by one by hand. The tradition dates to the seventeenth century, beginning when the Nanbu domain invited kettle-masters for the tea ceremony, four centuries ago. You can tour the foundries: the orange glow of molten iron, the craftsman's movements without waste. A place where tools made to last a lifetime are made.