Background: Paper is the most common substrate found in books and documents such as maps, manuscripts, and musical scores, though papyrus, parchment, palm leaves, plastic and other materials have also been used.
Specialists study the composition of paper and other substrates to identify documents at risk of deterioration or to authenticate questioned documents. Such studies can reduce risks to collections, while adding value to the knowledge of a document’s provenance and manufacture. Recognizing variations in types of substrates, through their respective optical, chemical and physical properties, can help specialists “date” documents, since certain materials, such as fibers and additives, were used at different times and places historically. In addition, specialists can estimate the stability, durability and longevity of paper-based materials, since some fibers, additives and manufacturing processes inherently weaken paper.
Reference collections of known and characterized paper samples can aid specialists in identifying unknown, unstable, or questioned documents and materials. The Library of Congress holds a collection of standard papers made from known fibers from the Technical Association of the Pulp and Paper Industry (TAPPI). This collection has long been used to provide reference samples to aid in the identification of fibers in papers found in conjunction with collections in libraries, archives and museums.
Project Description: To create an “atlas” of fibers, two sets of photomicrographs have been generated using optical microscopy and scanning electron microscope (SEM). Together, the two imaging techniques can characterize specific types of fibers. Optically generated images illuminate the internal morphology of fibers, while SEM images reveal external topographies.
Update: The image atlases are being digitized to enhance future access. The fiber specimens are being re-housed in an archival storage system for long-term retention in the Center for the Library's Analytical Science Samples (CLASS).
