The term “sunned” refers to light exposure causing the fade or lightening of book covers by sunlight. This phenomenon often affects hardcover books left near windows or outdoors and exposed to direct sunlight for extended periods. Overexposure causes ultraviolet rays from the sun’s rays to bleach out the color from their cover, leaving an old and worn look in its place. However, this won’t necessarily diminish its value to a collector. It does make the book less visually appealing.
Sunned refers to the gradual fade-away of book covers by exposure to sunlight, such as leaving them out in direct sunlight for too long or printing with inferior inks that do not offer UV resistance. Sunning may also refer to intentionally exposing books to remove their covers to sell them without their book covers intact.
Sunning is used to remove a book’s cover so it can be sold without it, and sometimes also used to age and discolor its cover intentionally, adding value and making the book more valuable for sale.
Sun damage to books or “sunned” books can be avoided in several ways. To preserve its condition, store it in a dark and cool environment; when displaying it in your home, ensure it’s out of direct sunlight. Alternatively, you could purchase UV protective book covers to further shield your books from sun damage.