I would say Kachin, based on the almost straight blade, concave tip, and the three-part grip with the fat middle. It looks like bone to me, too, but the way - too much grain to be ivory.
The basket weave on the scabbard is new to me, too. Very interesting.
About the "finger-prints" (excuse my Italion, folks, just trying to be clear) - vuoi dire le rosette lungo la spina, o proprio le macchie scure sulla lama? [translation for others - "do you mean the rosettes along the spine, or the dark stains on the blade?"] I think the rosettes are just decorative, though a similar mark is used in Thailand as a maker's mark, but only because I've never seen a maker's mark placed all along the blade like that. The stains on the blade are very likely real fingerprints, or rather oxidation caused by them.
All-in-all, its a really nice piece. Congratulazioni!
