1. What makes a book rare?
Millions of books, pamphlets, magazines, newspapers, and broadsides have been published since the invention of printing more than 500 years ago. Only a small portion of these pieces, however, would be considered "rare" by specialists. In simple terms, books achieve a degree of rarity only when demand exceeds supply. Unfortunately, there are no easy formulas for determining rarity.
People value books either because of their contents or because of their physical characteristics. First editions of important literary or historical works and initial reports of scientific discoveries or inventions are prime examples of books that are important because of their contents. Illustrated books that give a new interpretation of a text or are the work of an esteemed artist are also valued. Books that were suppressed or censored may be both important and scarce, since few copies may have survived. Physical characteristics, such as a special binding, an early use of a new printing process, or an autograph, inscription, or marginal annotations of a famous person, may also contribute to a book's importance and its market price.
A book known to exist in only a few copies may have significant monetary value if collectors prize it. Searching the Internet using services like bookfinder.com, AbeBooks.com, or ABAA.org can give you an idea of how many copies of a book are currently being offered for sale. However, a book without important text or distinguishing physical characteristics is likely to have little economic value, no matter how few copies survive.
Age by itself is not enough to make a book valuable. The importance of the text, the condition of the book, and demand for it will determine the valuation of an old book. However, certain categories of books are generally more sought after, including all books printed before 1501, English books printed before 1641, books printed in the Americas before 1801, and books printed west of the Mississippi before 1850.
Because books are portable and durable, rare books can turn up anywhere, from well-ordered private libraries to attics, basements, garage sales, and increasingly on Internet bookseller and auction sites. Books considered rare by collectors and librarians may be found together with more common books. Experience and specialized knowledge are often needed to discriminate among them.
A second-hand or used book is a previously owned book that is not an important edition and has no special physical characteristics, such as binding, provenance, inscription or association with important previous owners. Market prices for second-hand or used books are typically modest.
Condition refers to a book's physical appearance and the completeness of its contents. In general, the better a book's physical condition, the more it will be worth. A book in "fine" condition will be complete and show very little or no wear. A book with loose pages or a worn binding will be considered in "poor" condition. Missing pages or illustrations are a major fault that will make most books almost valueless.
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