Publicação
From Green to Brown
| Resumo: | In 2009–2014, new glass panels were produced by the Stained-Glass Studio of Canterbury Cathedral (UK) and installed in St Peter's Church (Little Barrington, Burford), St Lawrence's Church (Mereworth, Kent), and Canterbury Cathedral. After a few years, some spots and stains have appeared on the greenish areas of the panels. The common factor is that the panels were produced using the same green enamel. The present work reports on the studies of the observed alterations in green enamels to propose possible degradation mechanisms. These studies are based on using different analytical techniques such as optical microscopy, scanning electron microscopy energy dispersive X-ray spectroscopy, inductively coupled plasma mass spectrometry, laser-induced breakdown spectroscopy, X-ray diffraction, µ-Raman spectroscopy, profilometry, X-ray photoelectron spectroscopy, and UV–vis spectroscopy. The characterization of the fragments from the original panels showed that a brown layer of dark lead compounds was formed on the green enamel. The alteration occurred in a 3-step alteration mechanism divided into Pb2+ lixiviation from the enamel, formation of hydrocerussite (2PbCO3·Pb(OH)2), and transformation into scrutinyite (α-PbO2) and plattnerite (β-PbO2). |
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| Autores principais: | Palomar, Teresa |
| Outros Autores: | Calatayud, David G.; Oujja, Mohamed; Maestro-Guijarro, Laura; Aparicio, Mario; Mosa, Jadra; Koppermann, Bettina; Seliger, Léonie |
| Assunto: | alterations glasses green enamels leads stained-glass windows General Chemistry |
| Ano: | 2025 |
| País: | Portugal |
| Tipo de documento: | artigo |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade Nova de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório Institucional da UNL |
| Resumo: | In 2009–2014, new glass panels were produced by the Stained-Glass Studio of Canterbury Cathedral (UK) and installed in St Peter's Church (Little Barrington, Burford), St Lawrence's Church (Mereworth, Kent), and Canterbury Cathedral. After a few years, some spots and stains have appeared on the greenish areas of the panels. The common factor is that the panels were produced using the same green enamel. The present work reports on the studies of the observed alterations in green enamels to propose possible degradation mechanisms. These studies are based on using different analytical techniques such as optical microscopy, scanning electron microscopy energy dispersive X-ray spectroscopy, inductively coupled plasma mass spectrometry, laser-induced breakdown spectroscopy, X-ray diffraction, µ-Raman spectroscopy, profilometry, X-ray photoelectron spectroscopy, and UV–vis spectroscopy. The characterization of the fragments from the original panels showed that a brown layer of dark lead compounds was formed on the green enamel. The alteration occurred in a 3-step alteration mechanism divided into Pb2+ lixiviation from the enamel, formation of hydrocerussite (2PbCO3·Pb(OH)2), and transformation into scrutinyite (α-PbO2) and plattnerite (β-PbO2). |
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