Vellum

Vellum (derived from the Latin word vitulinum meaning "made from calf", leading to Old French vélin, "calfskin") is prepared animal skin or "membrane" used as a material for writing on. Parchment is another term for this material, and if vellum is distinguished from this, it is by vellum being made from calf skin, as opposed to that from other animals, or otherwise being of higher quality. Vellum is prepared for writing or printing on, to produce single pages, scrolls, codices or books.

Vellum is generally smooth and durable, although there are great variations depending on preparation and the quality of the skin. The manufacture involves the cleaning, bleaching, stretching on a frame (a "herse"), and scraping of the skin with a crescent-shaped knife (a "lunarium" or "lunellum"). To create tension, scraping is alternated with wetting and drying. A final finish may be achieved by abrading the surface with pumice, and treating with a preparation of lime or chalk to make it accept writing or printing ink.

Modern "paper vellum" (vegetable vellum) is a quite different synthetic material, used for a variety of purposes, including plans, technical drawings, and blueprints.

In Europe, from Roman times, the term "vellum" was used for the best quality of prepared skin, regardless of the animal from which the hide was obtained, calf, sheep, and goat all being commonly used (other animals, including pig, deer, donkey, horse, or camel have been used). Although the term derives from the French for "calf", animal vellum can include hide from virtually any other mammal. The best quality, "uterine vellum", was said to be made from the skins of stillborn or unborn animals, although the term was also applied to fine quality skins made from young animals. There has long been, however, much blurring of the boundaries between these terms. In 1519, William Horman could write in his Vulgaria: "That stouffe that we wrytte upon, and is made of beestis skynnes, is somtyme called parchement, somtyme velem, somtyme abortyve, somtyme membraan." Writing in 1936, Lee Ustick explained that:

To-day the distinction, among collectors of manuscripts, is that vellum is a highly refined form of skin, parchment a cruder form, usually thick, harsh, less highly polished than vellum, but with no distinction between skin of calf, or sheep, or of goat.

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