Thank you for sharing Jos.
Lots of interesting research still to be done on this piece, in particular the Coin motif in the blades. Here is a pair of knives I have in my collection of Chinese weapons
http://www.swordsantiqueweapons.com/s064_full.html
They share the same coin inlay, though mine show it in the blade and the hilt.
Whilst Klas notes yours as maybe being north China I ask, would a Muslim minority display Taoist symbols??? The knives I show are most definately south China in origins though who really knows with trade and such, mine could have been fashioned in the north under direction of someone who came from the south or yours could have been made in the south under direction of someone from the north, such if the global village of old as it is today.
I would love to see other examples of this type of dao and or the coin inlay in blades or hilts.
Show em if you got em good peoples.
Gav