corner-and-edge-grading

name	corner-and-edge-grading
description	Use when assessing the four corners and four edges. Maps what 'sharp', 'soft', 'fraying', and 'whitening' mean across grader rubrics.

Corner and Edge Grading

Each corner gets graded independently then averaged. Edges are walked under angled light. Black borders penalize hardest.

Corner condition tiers

Tier	Visible at	Grade
Razor sharp	Perfect 90° at 10×	10
Sharp	90° with imperceptible factory rounding	9
Slight soft	Tiny rounding at 10×	8
Visible soft	Rounding to naked eye	7
Dinged	Bent/crushed	≤6

Edge defect families

• Edge chipping — tiny missing laminate flecks (black-border curse)
• Edge whitening — white cardstock showing through colored border
• Edge fraying — fiber visible (handling damage)
• Print-line on edge — vertical print line can mimic chipping

The black-border tax

Black-bordered cards (Bowman Chrome, Pokemon, modern MTG) are penalized hardest because edge whitening is most visible. A black-border 9 ≈ non-black 10 in collector value. Submit only when all four edges look pristine — most 'mint' raw black-borders grade 8.

Where this fits in the X3 empire

Used by CardPrepAI's edge-walker tool to flag black-border submissions where the upside doesn't justify the fee.