From The Art and Popular Culture Encyclopedia
Parchment is a thin material made from calfskin, sheepskin or goatskin, often split. Its most common use was as a material for writing on, for documents, notes, or the pages of a book, codex or manuscript. It is distinct from leather in that parchment is limed but not tanned, therefore it is very reactive with changes in relative humidity and is not waterproof. The finer qualities of parchment are called vellum.
According to the Roman Varro, Pliny's Natural History records (xiii.21) that parchment was invented under the patronage of Eumenes of Pergamum, as a substitute for papyrus, which was temporarily not being exported from Alexandria, its only source.
Herodotus mentions writing on skins as common in his time, the 5th century BC; and in his Histories (v.58) he states that the Ionians of Asia Minor had been accustomed to give the name of skins — diphtherai — to books; this word was adapted by Hellenized Jews to describe scrolls . Parchment (pergamenum in Latin), however, derives its name from Pergamon, the city where it was perfected (via the French "parchemin"). In the 2nd century B.C. a great library was set up in Pergamon that rivalled the famous Library of Alexandria. As prices rose for papyrus and the reed used for making it was over-harvested towards local extinction in the two nomes of the Nile delta that produced it, Pergamon adapted by increasing use of parchment.
Writing on prepared animal skins had a long history, however. Some Egyptian Fourth Dynasty texts were written on parchment. Though the Assyrians and the Babylonians impressed their cuneiform on clay tablets, they also wrote on parchment from the 6th century BC onward. Rabbinic culture equated a "book" with a parchment scroll. Early Islamic texts are also found on parchment.
One sort of parchment is vellum, a word that is used loosely to mean parchment, and especially to mean fine parchment, but more strictly refers to parchment made from calfskin (although goatskin can be as fine in quality). The words "vellum" and "veal" come from Latin vitulus, "calf", or its diminutive vitellus. In the Middle Ages calfskin and split sheepskin were the most common materials for making parchment in England and France, while goatskin was more common in Italy. Other skins such as those from large animals such as horse and smaller animals such as squirrel and rabbit were also used. Whether uterine vellum (vellum made from aborted calf fetuses) was ever really used during the medieval period is still a matter of great controversy.
There was a short period during the introduction of printing where parchment and paper were used interchangeably: although most copies of the Gutenberg Bible are on paper, some were printed on parchment. In 1490, Johannes Trithemius preferred the older methods, because "handwriting placed on parchment will be able to endure a thousand years. But how long will printing last, which is dependent on paper? For if ...it lasts for two hundred years that is a long time."
In the later Middle Ages, parchment was largely replaced by paper. New techniques in paper milling allowed it to be much cheaper and more abundant than parchment. With the advent of printing in the later fifteenth century, the demands of printers far exceeded the supply of animal skins for parchment.
The heyday of parchment use was during the medieval period, but there has been a growing revival of its use among contemporary artists since the late 20th century. Although parchment never stopped being used (primarily for governmental documents and diplomas) it had ceased to be a primary choice for artist’s supports by the end of 15th century Renaissance. This was partly due to its expense and partly due to its unusual working properties. Parchment consists mostly of collagen. When the water in paint media touches parchment’s surface, the collagen melts slightly, forming a raised bed for the paint, a quality highly prized by some artists. Parchment is also extremely affected by its environment and changes in humidity, which can cause buckling. Some contemporary artists also prize this quality, noting that the parchment seems alive and like an active participant in making artwork. To support the needs of the revival of use by artists, a revival in the art of making individual skins is also underway. Handmade skins are usually better prepared for artists and have fewer oily spots which can cause long-term cracking of paint than mass-produced parchment. Mass-produced parchment is usually made for lamp shades, furniture, or other interior design purposes.
The radiocarbon dating techniques that are used on papyrus can be applied to parchment as well. They do not date the age of the writing but the preparation of the parchment itself. However, radiocarbon dating can often be used on the inks that make up the writing, since many of them contain organic compounds such as plant leachings, soot, and wine.