ABSTRACTThe oldest known fragment of a codex was discovered at Graz University Library and made public in June 2023. The so-called ‘Mummy Book’ shows features – a central fold, text layout, ink transfer and holes – that distinctly identify it as a bifolio from a codex-like structure. These characteristics are described here and their significance is summarized from our longer research article. By examining these features, we were able to reconstruct the history and use of the fragment. The results are significant because they identify the fragment as the oldest known bifolio, predating similar examples by 400 years. Although no comparable material from this period is known, the Mummy Book is evidence for the existence of pre-Christian codices, substantially changing the history of the book. We hope that collections will be systematically examined under this lens to unearth further examples providing a clearer chronology of book history before Christ.