I'm trying to hone a NOS 7/8 fili, and it's being problematic.

There's a 1 cm area towards the heel that wants to form a wire edge off of everything finer than a 4k.

I set the bevel on a 1.2k, and have no problems on my freshly lapped Norton 4k, however when I try honing on anything finer, this area forms a wire edge. (within 5 passes)

I've tried my norton 8k, my transparent arkansas, even my kitayama 12k...
no pressure, all of these hones were freshly lapped.
Even using a pasted strop causes this spot to foul up.

I have tried everything I can think of from honing at a 45 to a Zowada style double bevel. This area will not take an edge.

My thoughts at this point are that the metal is flawed in this blade, or that there was a problem with it's heat treatment.

As this is something I've never encountered(in a straight razor), I figured I would run it by the group.

Any ideas or suggestions?