Browsing by Author "Kjaer, Ulla"

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    Investigations of the relics and altar materials relating to the apostles St James and St Philip at the Basilica dei Santi XII Apostoli in Rome
    (Springer, 2021-01-29) Rasmussen, Kaare Lund; van der Plicht, Johannes; La Nasa, Jacopo; Ribercini, Erika; Colombini, Maria Perla; Delbey, Thomas; Skytte, Lilian; Schiavone, Simone; Kjaer, Ulla; Grinder-Hansen, Poul; Lanzillotta, Lautaro Roig
    Two types of materials were sampled as part of an investigation of the relics of the Holy Catholic Church of the Apostles St Philip and St James in the Basilica dei Santi Apostoli in Rome: bone‑ and mummy‑materials and architectural samples. The analyses encompassed radiocarbon dating, thermoluminescence dating, gas and liquid chromatographic separation with mass spectrometric detection, X‑Ray fluorescence, X‑Ray diffraction, inductively coupled plasma mass spectrometry, Raman spectroscopy, and Fourier transform infrared spectroscopy. The results show that the samples were subjected to a number of conservational and exhibition‑related treatments. The alleged femoral bone of St James was dated between AD 214 and 340 (2σ confidence), which shows that this cannot be the bone of St James. An encrustation found in a canal in the reliquary in the high altar construction showed the presence of heavily oxidized rapeseed oil, which was radiocarbon dated between AD 267 and 539 (2σ confidence), and a ceramic shard also found in the high altar construction was TL‑dated to AD 314–746 (2σ confidence). The two latter dates are consistent with a translation of the relics following the erection of the church at the time of Pope Pelagius I in AD 556–561
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    Release of lead from Renaissance lead-glazed ceramics from southern Denmark and northern Germany: Implications from acetic acid etching
    (Springer, 2020-05-18) Rasmussen, Kaare Lund; Milner, George R.; Delbey, Thomas; Jensen, Lisa Kathrine Ivalu; Witte, Frauke; Rehren, Thilo; Kjaer, Ulla; Grinder-Hansen, Poul
    Lead-glazed potsherds from archaeological excavations at six Renaissance (1536–1660 CE) sites in southern Denmark and northern Germany have been subjected to etching experiments using 4 wt% acetic acid. The extracts of 45 sherds were analysed by Inductively Coupled Plasma Mass Spectrometry. At one site, the ducal hunting castle of Grøngaard, Pb levels in acid extracts from glazed dishes were so high (up to 29,000 µg Pb cm−2 day−1) that acute toxic effects likely occurred if the dishes were used for serving food containing vinegar. More moderate acid-etching Pb levels were found in dishes from other sites, but they still exceed the WHO critical level if used daily. Acetic acid etching experiments performed on pipkins (three-legged cooking pots with a handle) yielded somewhat lower Pb extract values, averaging ca. 25 µg Pb cm−2 day−1. Taking into account the widespread use of pipkins for cooking, they might easily have led to a higher weekly Pb intake than the use of the moderate-level dishes. The question remains whether such high levels of Pb exposure during meals led to injurious Pb intake. Prior skeletal analyses have shown that medieval to early modern individuals from the area, especially in towns, were exposed to Pb. While exposure could have come from various sources other than lead-glazed ceramics, such as cosmetics, paint, antibacterial ointments, and lead water pipes, widely distributed lead-glazed ceramics had the potential of being a main source of Pb. How the pottery was actually used is uncertain, and it certainly was not evenly distributed across all segments of society, but the etching experiment results suggest that severe poisonous effects could have resulted from the use of lead-glazed Renaissance ceramics.