Notes:
The tiny scratches from harsh cleaning are usually not visible to the naked eye and mostly not visible under low and medium magnification. It depends on the fineness of the brush, intensity, duration, pressure applied, etc. Under high quality 15X magnification, if the coin is held in the light at just the right angle and moved about, most any tiny scratches can be seen in families running in different directions. You can even see whizzing marks at 15X. The scanner I use is largely incapable of capturing these fine lines, and only sometimes catches the larger ones if they are running perpendicular to the light source. This type of harsh (and gentle) cleaning is/was rampant to make coins look shinier and brighter and remove purse slime, debris, tarnish, dark toning, spots, staining, corrosion, etc.