RW13a, bright rose pink color error, turned out to not be an error at all, but a chemically altered changeling. After several decades and thousands of dollars changing hands, modern technology was finally able to prove that this error never existed. The listing was removed from the Scott Specialized Catalogue of United States Stamps and Covers in 2016.

Read More: “RW13a” is a Chemically Induced Color Changeling – Waterfowl Stamps and More