Dug WWI Polish button relic for military army infantry uniform - #1 conserved For Sale

Original; cleaned and conserved by me (former professional museum conservator).
I have terrible eyesight, so I can work with the materials only a few hours per day and under extreme magnification.
Mechanical cleaning methods are all I use (never chemicals).I do sometimes coat the artifacts in a neutral microcrystalline wax, but only if required and it will be noted in the description.
Exact recovery site unknown; as shown. US quarter shown for scale.
From a smoke-free home.

I am visually disabled. If I miss something, it is NOT intentional.