Vintage Japanese Nambu Tekki (Nanbu Tekki) cast iron teapot

Vintage Japanese Nambu Tekki (Nanbu Tekki) cast iron teapot, most likely manufactured by Iwachu, the most famous foundry in Morioka, Japan. Holds one cup. • The vertical characters stamped under the spout (shown in second image) are typical of the Iwachu (岩鋳) foundry. Iwate Prefecture, the home of Nambu ironware. • Pattern: This classic "hobnail" design is the most iconic Nambu Tekki pattern, designed to increase the surface area and heat retention of the iron. • Teapot for keeping tea hot. Suggested not to put on stove or fire. Pour hot water into kettle. Holds one cup of tea. Inside is enamel coated but there are signs of rust and wear (as seen in pics). It’s from 1970-1980…Great collectors antique piece!