Book Collecting - Condition

Condition

Further information: List of used book conditions

As with other collectibles, the value of a book ultimately depends on its physical condition. Years of handling, moving, and storage take their toll on the dust jacket, cover, pages, and binding. Books are subject to damage from sunlight, moisture, and insects. Acid from the papermaking process can cause the pages to develop brown spots, called foxing; gradually turn brown, called tanning; and ultimately crumble.

Common defects include general wear; jacket/cover edge wear, scratches, and tears; the previous owner's written name, Bookplate, or label; soil and stains; dogeared pages; underlining, highlighting, and marginalia; water damage; torn hinges, endpapers and pages; and pages, illustrations, or whole signatures free of the binding, or missing entirely.

A book in good condition should be a rectangular solid when at rest, whether upright or on its back, with the covers at right angles to the spine. If a book is out of square, usually from resting crooked on a shelf, or leans to the right or left when on its back, it is cocked, or shelf-cocked. If the covers bend in or flare out, usually from rapid humidity changes, a book is bowed (bent like a drawn bow). Thick hardbound books also tend to have their pages sag downward in the middle even if they are sitting level on a shelf.