animal skin processed for writing or painting on
Parchment is a writing material made from specially prepared untanned skins of animals—primarily sheep, calves, and goats. It has been used as a writing medium for over two millennia. Vellum is a finer quality parchment made from the skins of young animals such as lambs and young calves.
It may be called animal membrane by libraries and museums that wish to avoid distinguishing between "parchment" and the more-restricted term "vellum" (see below).
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