Complete replacement of a unique item is therefore impossible. While most library materials come to the library ready to use, curators must do extensive preparatory work before the materials are ready for patron use. They begin preservation work on collections by improving the immediate environment of the materials and by providing protection the materials will need to survive usage. The earliest steps consist of removing harmful materials from contact with the documents. Metal paper clips and staples frequently rust, and the resulting iron oxide invades the paper.
Staples weaken the paper.
Without staples, people are less likely to fold papers. Curators remove the staples and metal paper clips to prevent further damage. When it is important that materials be fastened together in order to preserve an association among documents that might otherwise be lost, curators use inert plastic clips. Some items arrive at the repository stored in a highly acidic environment. Photographs mounted in a scrapbook, paper records covered in construction paper, items reproduced by early duplicating technologies such as thermofax and items stored with clippings from newspapers, exemplify some problems archivists often find.