RINGS OF SATURN?

No way - it's the soundhole of a Japanese Aria jumbo guitar. Terrible photo of a ghastly instrument!

Needed to remove the pick-guard (in this case, an ugly piece of plastic glued to the table designed to protect the table from idiots with plectrums (picks)).

Having softened it with white spirit - took me an hour and a half to remove most of the glue with a piece of sharpened ebony. Got rid of the residue with acetone -  luckily these guitars are varnished with the dreaded polyurethane which is impervious to acetone!

I'll get off my high horse OK?