The most precious masterpiece of the earliest Christian art of printing, as all book-lovers seem to agree, is Gutenberg's Bible in Latin. The choicest of all the forty-five specimens of Gutenberg Bibles still remaining in existence (so most connoisseurs of early printing likewise agree) are the twelve printed on vellum. Of this famous first and only parchment edition there remain but three perfect specimens of the complete Scriptures.
Why? 1- superb typographic legibility and texture, 2- generous margins, 3- excellent presswork.