Originally Posted by ghostrider

The reason they looked different is because the grain was running perpendicular to itself where the horizontal and vertical borders met. It's because of the way light reflects off the weave and has nothing to do with the dye. All fabrics do this, it's just more obvious with dark solid broadcloths like Kona Solids.

To prevent it from happening again, make sure the grain runs the same way in the finished quilt...which means cutting the side borders on one grain (lengthwise) and the top and bottom ones on the other (crosswise).