I'd like the communities input on how I should go about perhaps creating these weapons. The bone they will be made from is from a Khornite daemon and there will be 2 swords, 1 staff, and 1 knife. I have a basic idea of how I want them, but fellow game master ideas never hurt. Note: They are only rank 3 at the moment and I don't foresee them getting the weapons back until rank 6 or so.

Just use the daemon weapon rules in Radical's handbook, start with the template of a weapon with roughly the right stats and abilities and go from there.

Indeed, I would follow the daemon weapons as well - doubly so since daemon's dont really have bones (they are shaped warp-stuff, and dissipate when they die) they would have to be chaotic artifacts in the first place. Possibly even shaped daemons.

Granted, GM fiat and all - if one wants to do it its easy enough to make ways around that.