Centering55/45 or better on the front. 70/30 or better on the back.
CornersModerate wear on corners, with fraying & chipping. Noticeable by the naked eye and more pronounced under magnification.
EdgesLight to moderate chipping, wear, & minor nicks visible under inspection. Edges remain generally clean and intact.
SurfaceExtensive damage including deep creases, heavy scratches/micro-scratches, stains, and surface residue.