Corners are the first thing a PSA grader looks at. If they aren't sharp, the rest of the card doesn't matter. But not all "imperfect" corners are damage.
What is "Micro-Whitening"?
Micro-whitening involves tiny fibers of the white card stock showing through the colored ink at the very tip of the corner. It usually happens from handling or bouncing around in a box.
Grade Impact Table
| Defect | Resulting Grade |
|---|---|
| No Whitening (Razor Sharp) | Gem Mint 10 |
| 1 Corner with Micro-Whitening (Visible under Loupe only) | Mint 9 (Usually) |
| 1 Corner with Spec Visible to Naked Eye | NM-MT 8 |
| Rounded / Soft Corner | EX-MT 6 or lower |
Factory Roughness vs. Damage
Some sets (like 1980s O-Pee-Chee or modern Panini Prizm Die-Cuts) have "rough cuts" from the factory wire blades. This is NOT always damage.
Rule of Thumb: If the roughness is uniform along the entire edge (a "fuzzy edge"), PSA is lenient. If it is a specific ding or impact on one spot, they punish it.
The "Black Mat" Test
To see edges clearly, place the card on a piece of black velvet or a dark mousepad. The contrast makes the white paper fibers pop out immediately. You will be shocked at what you missed against a white desk.