This is a high-quality Jitte or a Sengoku-era Kabutowari (helmet breaker). I haven't seen many Jitte longer than this one, which is 59 centimeters long and therefore quite heavy. There are also traces of impact marks from actual use, so the person struck with this must have been in considerable pain. Items with this level of carving and craftsmanship would have only been used by people of high rank. Originally, the tip would have been pointed, but perhaps because it lacks the characteristic hook of a Jitte, it's called a Kabutowari, used to strike a warrior's head, helmet and all, causing a concussion. The black rust on the iron, a result of aging from the Edo or Sengoku periods, is well-developed, and the surface is coated, so I don't think any more red rust, a major enemy, will appear. This is a valuable Jitte or Kabutowari, much like a Japanese sword. I think it's a treasure for enthusiasts. Thank you.