This is a peculiar cup, with a thin iron plate forming the base and a thin layer of brass covering the inside. It's unlike a confectionery mold. While some items, like tin products, are designed with a space to prevent the heat from hot tea from reaching the hand, making them easier to handle, I've never seen this design made with the difficult-to-work-with materials of iron and copper. It doesn't seem like it would make drinks like sake or tea taste any better, so it's a piece for a quirky individual. The work itself is laborious, but it's interesting. As shown in the photo, there are faint letters or alphabets stamped on the iron base, but I can't read them. Diameter is approximately 5.6 cm. Height is approximately 2.6 cm.