A protective box designed for storing and preserving a bound book or loose sheets. A clamshell box is hinged on one side, with the remaining three sides of both the top and bottom of the box extending in such a way that one side neatly fits into the other when closed. Clamshell boxes are used for archival and decorative purposes in library archives and the rare book trade to protect delicate bindings or to house pages of loose manuscripts and other unbound materials. Often a clamshell box will be custom fit by a binder for a a specific volume, fitting it precisely and decorated to convey the character of the content, sharing many of the same traits as fine book binding. Clamshell boxes can also be prefabricated for archival purposes in libraries and institutions.