Strike-through error? Repeating circles

Has anyone seen this on a Seychelles or other coin? It is a pattern of circles throughout the entire planchet, both sides, and 90+% of the pattern has survived the striking process.

N#19424

edit: retitle thread

Looks like a strike through error. Something (paper, piece of fabric) gets between die and planchet and transfers texture to coin.

Is it texture or just surface oxidation? I had some cheap privately packaged coin sets that left similar marks on some coins.

P.S. also nice macro pictures, what is your setup?

The pattern is on both sides pretty evenly.

I like the theory of the textured vacuum plastic. Add some heat, and a few years in a window, then peel away the plastic…

It does not appear to be a transfer of of plastic.  I cannot alter the pattern with a steel blade tip or with acetone.  It is permanently pressed into and is now part of the entire coin pattern. The strike-through idea seems most likely, IMO.

edit: Dino-lite USB microscope