Thank you all for replies! Now about etching: after the blade was polished several times with 600 grit wet paper (with oil) I have used 75 % Phosphoric Acid. After 5-10 minutes of etching the blade was ready. Then again a very light polish (with 1000 paper and oil) was applied to make the blade surface shining and transparent. The Damascus steel is now like a 3D picture ( if you see, what I mean) and really beautiful, but it is impossible to show on the pictures. To make the "flashy "pictures above (to show better the steel pattern) I have used a very strong contrasting tool in Photoshop (I love Photoshop
), but in reality the pattern is seen only under correct light and angle and is subtle, like hada and hamon on Japanese swords. The picture nearest to reality is third from top, where you can see the whole sword.
The interesting feature to me is that the blade construction looks like on old Indonesian Keris: it has a core steel (it is easy to see near the cutting edge) which is covered by the layers of the Damascus Steel. Maybe it is the same as inserted edge that the Marc talks about. And about Damascus pattern and the sword itself (its origin, name and age) I would like to hear some replies from specialists too, because that was really the theme of this thread. To me it looks and feels like a real old sword, which has seen some use during its life
(see description above)