Background: Documents, such as maps, manuscripts, musical scores, and other materials, are made of various substrates, such as paper, papyrus, parchment, plastic or other organic or inorganic materials. Paper is the most common substrate found in documents.
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 are being 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: Hardwoods, such as Mountain Ash, White Ash, Aspen, Birch, Lingnumvitae, Oak, and Poplar, have been imaged for the atlas.
