Debris found in I R D oil

51 Plate TD4
48.000 miles full history

After returning from a 50 mile round trip yesterday I decided to drop the oil in the I R D ( mistake ) the oil seemed to be clean but when i cleaned out the container with the oil oil in I found what looks like a brass shim suspect it is from the diff gears. the car is running perfect no noise at all

Should i keep running it or would you strip the unit to investigate.

Many thanks

You sure its not the nut washer?

Pic would be useful

fingers crossed
after a sleepless night and loads of head scratching I hope the debris in the container was from a previos job i did on a Daf 45 lorry that did have a diff problem

thanks Northern Irelander!!