It was from a 100pc T-Y 52X CD-R spindle purchased at blankmedia.ca. I checked through the other 99 discs and none of them had this problem. The one in the photo was #2 on the top of the spindle.)
That is quite a defect.
I can’t say what caused it exactly, but many people have noticed that discs at the very top of the spindle are some times lower quality and/or have a higher chance of being defective.
This must be due to higher exposure to light / heat / other environmental variables, etc…
Hm yes, the ones at the top of the spindle were slightly more ‘wobbly’ in the definition of the inner ring of ink, but the ones lower down were very smooth and consistent.
Speaking of top of the spindle defects…
I recently got a 50 spindle of BenQ 8X DVD-R (SONY08D1).
The top disc is defective.
Notice the large air bubble in the stacking ring.
This blank disc is not recognized in any drives.