The Illusion of Newton’s Rings

The physics behind this curious phenomena

Grading and encasing with Rare Edition is a process collectors seek to not only give them security and peace of mind, but also to ensure they are receiving an authentic grade and the best protection for their most valuable collectibles. This protection comes from a combination of polycarbonate, Corning® Gorilla® Glass, a synthetic bumper, and the tight tolerances we machine our cases to.

One of the rare side effects of this protection is a phenomenon known as Newton’s Rings.

The differing thicknesses of air between the two surfaces creates a pattern of constructive and destructive interference with the light waves

Some of our collectors may see this visual illusion on their slabs, which they may not have seen elsewhere in the hobby. Very rarely, our polycarbonate can end up with a slight convex curvature to it. Without any additional material this very slight curvature would go unnoticed, but when this material comes very close to a flat (our Gorilla® Glass) surface, the differing distances between the polycarbonate and the glass produces this phenomenon.

As the two surfaces come near to each other the differing thicknesses of air between the two surfaces creates a pattern of constructive and destructive interference with the light waves. As the distance between the polycarbonate and the glass varies, you’ll see brighter areas (like a reflection) where the light reinforces itself, and darker areas (like a shadow) where the light cancels itself out. This results in the characteristic “rainbow” effect you can see in the image above.

This illusion may make it appear as if moisture, oil, or a bubble is trapped inside our slab. We can assure you that that is not the case (pun intended). We use ultrasonic welding to create exceptional encapsulation without adhesive or glue. While the glass is stuck on using a clear adhesive, it is strictly on the edges and no liquid or bubbles can exist in the middle of the card.


While this issue occurs only rarely in our process and we catch the vast majority before they leave our office, it is possible that you may find it on your case. If this is something that bothers you, please contact our support team and they will work with you to get your case re-encased. And above all, know that your item is still 100% dry and protected in the world’s best slab no matter what.

Got any other questions about our case or our processes? Reach out to us on Social Media or contact our support team!