Machete ? Agricultural tool ?

[thomas hauschild]

Don‘t know what this (20€)-find could be. 64 cm length, very thin (2 mm) and flexible blade.
-The back of the blade is nearly sharp with a convex shape. Maybe to swing forwards and backwards ?
- A tang that I never saw before. ( grip is loose and only fragments left)
- a forging mark
- raffinated steel, more hardened at the front ( black etch)

Any comments welcome and Admins feel free to move the post.

Best Thomas