Abstract: A placemark has mutually magnetically attractive surfaces disposed opposite one another. The magnetic surfaces are connected to each other by a flexible connecting web, such that they can be separated from each other and closed again on opposite sides of a sheet, for example a page of a book. The placemark is held in position on the sheet by the force of the magnetic attraction between the magnetic surfaces. Thus, the magnetic surfaces grip the periphery of the sheet between them. The placemark further comprises preferably a marker web which extends from the connecting web.