Inks from Herculaneum Papyri

The Herculaneum papyri (Fig. 1), comprising nearly 1,000 rolls of papyrus that were carbonised during the eruption of Mount Vesuvius in 79 CE, represent a significant collection of ancient manuscripts (Delattre 2006; Longo et al. 2020). While mechanical methods, particularly those developed by Antonio Piaggio, have enabled the successful unwrapping of certain rolls and fragments (Angeli 1995), current efforts are prioritising virtual unwrapping through computed tomography (CT-scanning). This approach minimises the risk of irreparable damage to the delicate papyri (Allegra et al. 2016). To effectively utilise CT-scanning on the scrolls, a strong chemical contrast between the ink and the papyrus substrate is essential. Unfortunately, the use of pure carbon ink on charred papyrus presents challenges in achieving this contrast. However, recent findings regarding the presence of metallic additives in carbon inks (see Mixed Inks) used on Hellenistic and Roman papyri (Delange et al. 1990; Brun et al. 2016; Christiansen et al. 2017) have sparked optimism that some Herculaneum papyri may similarly contain metal traces, which could provide the necessary contrast. A preliminary analytical campaign with X-ray fluorescence, with the XRF spectrometer Elio from Bruker / XGLab (Fig. 2) conducted at the Biblioteca Nazionale di Napoli on selected fragments has confirmed this possibility, successfully identifying fragments with inks which contain phosphorus (P), iron (Fe), copper (Cu) and / or lead (Pb) (see What Is My WA Made Of?). These fragments are good candidates for future CT-scanning efforts (Bonnerot et al. 2020; Bonnerot et al. 2021) (see Can the Damaged or Hidden Writing From My WA Be Made Visible Again?).

Fig. 1: unwrapped roll fragments from herculaneum on display at the Biblioteca Nazionale di Napoli.

Fig. 2: Elio XRF spectrometer setup during the analyses at the Biblioteca Nazionale di Napoli.

References

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