Similar question, but mine are certainly not antique, made of carbon steel, and they appear crudely finished along the non-cutting surfaces. Second picture shows cavity/void along cutting surfaces, which along with the maker's mark I thought would be quick and easy for someone here to ID.
I picked these up for hardly any money, and I suspect these are cheap-o's, but I thought I'd check here and see if anyone could confirm this for me.
They do cut well and there's zero play, so pretty happy with them considering the "shear" number of tools I got as part of a large set (Bunch of Kiku cutters came with the set) and for such little money.