Which kind of steel is this ?

[Martin Lubojacky]

The blade (cca 60 cms long and originally very rusty), was mechanically cleaned, plunged into disodium salt of EDTA and again cleaned with a very fine steel brush, than cleaned in demi water and treated wit silicon oil.

I think the steel is not mechanical damascus, actually, I don´t know what to think about it. If I cleaned it too much deep, the structure(design) disappeared on some places (tip and near the tip). What is this ? I heard such design could be result of tempering (quenching), but I am not sure. (the handle is original except of the central rhomb rivet which is new).

[ALEX]

Martin, I do not see/think it has any particular pattern, although I see one weak streak, but hard to tell. extensive pitting and mechanical cleaning do weaken the pattern and make it harder to etch.

[Iain]

I have to say it looks like mono steel to me, simply exhibiting aging due to exposure to dust/dirt etc.

[Gavin Nugent]

The type is known to have a twist core centre within the very narrow fullers but nothing gives it away if it is there.

[Oliver Pinchot]

These blades are often layered, which etching may reveal. But it isn't an intentional pattern-weld. I'd leave it as is or perhaps clean lightly.