Seller says it is from Edo period, that is quite a broad range in age. it seems Shinshinto to me; we had a discussion about these types of swords several months ago, though i can't remember names of smiths who did this style. As for the polish, i am baffled, as the laminations within the hamon area are shiny while the overall area is frosty. I would not know how this was done; I am doubting that an acid process can result in this appearance, but i could be wrong. It has its own unique beauty for what it is, a very nontypical sword.