kindjal - what kind of technique is it ?

[ariel]

Acid-etching within the fullers is esthetically appealing and structurally safe.
But the more I look at the first one (total blade etching), the less I like the potential effects on the edge: seems to me that acid ate through quite a lot of steel and some areas of the edge became thin and prone to breaking. This is likely the cause of many "non-traumatic" nicks.