Art? science? .... Alchemy : the materiality of spiritual expression in artistic creation revealed through the analytical techniques of a heritage conservator

To the uninitiated, it is quite probable that the results that art conservators derive from analytical techniques, may resemble alchemy, but they do not create gold from lead. Instead, they represent the composition of an object as its chemical components. X-ray fluorescence spectroscopy (XRF) has long been used for the compositional determination of minerals and metals in the mining and manufacturing industries, and over the past few years the applications in art and conservation increased rapidly. In addition, technical photography (in which filtering determines which wavelengths of light reach the camera) has the ability to create a new art form – one that, apart from being visually appealing, can provide information on the materials which had been used by the artist. In this manner, a whole new layer of information may be revealed, adding to the aesthetic and spiritual impact of the work. In this article, two objects of African art, namely a century-old prayer scroll from Ethiopia and a two-decades old sculpture by South African artist Lucky Sibiya, are investigated to see if this ‘alchemy’ can reveal that which even the artists were unaware of.The South African National Institute for the Humanities and the Social Sciences (NIHSS).http://www.pharosjot.comam2022Visual Art

Energy requirement for firing porcelain

Results from studies on the ternary system Ribaué kaolin–Carapira feldspar– Marracuene quartz sands were used to test a procedure that we developed for calculation of the energy requirement for firing porcelain. Results obtained vary between 1300 and 1800 kJ/kg porcelain. These results differ largely from the ones obtained using Hennicke’s procedure. KEY WORDS: Porcelain, Energy requirement for firing porcelain, Kaolin---feldspar---quartz sandsBull. Chem. Soc. Ethiop. 2004, 18(1), 73-80

Combining XRF and XRD analyses and sample preparation to solve mineralogical problems

X-ray Fluorescence Spectroscopy (XRF) has reached the stage where it is classified as a mature analytical technique. The theoretical principles are well understood. In addition modern instrumentation demonstrates enhanced generator and temperature stability. High sensitivity is possible even for light elements and effective matrix correction software is available to the modem day spectroscopist. Apart from its continued applications in research and development, XRF has become u routine process control tool. X-ray Powder diffraction (XRD), on the other hand, has with minor exceptions as in the cement industry, largely remained a research tool, despite being an older analytical technique than XRF. XRD has progressed significantly in the past decade from a mainly qualitative technique for the identification of crystalline materials to a quantitative tool with the advance of more powerful software packages. This software has improved instrument control, but also quantification and structure determination using the Rietveld method. Consequently, XRD is rapidly entering the process control environment. In this paper the authors demonstrate, with practical examples from different industrial applications, how combined XRF and XRD use can provide truly quantitative phase analyses. XRF is used to verify XRD data and visa versa. The data obtained in this study clearly illustrate the value that can be added to either technique if XRF and XRD data are used together, and indicate some applications in routine process co

Potential pesticide contamination in repatriated artifacts in African museums : the need for the adoption of safety protocols for access and use of hazardous artifacts

This article discusses the issue of potential pesticide contaminants in artifacts that are being repatriated by museums from the global north to Africa. It highlights that the issue of scientific testing of artifacts for harmful pesticide contaminants is missing from the repatriation discourse in African museums. Consequently, safety protocols for handling and use of these potentially contaminated artifacts have not been established in some African museums. This is worsened by lack of legislations that enforce the testing of the artifacts and the establishment of safety protocols for accessing them. This exposes museum staff, researchers and other visitors to health effects caused by toxic chemicals in artifacts. In light of this, the article recommends that repatriation of artefacts to African museums should be preceded by scientific testing of artifacts to determine the possible toxic pesticide contaminants on them, and to establish safety protocols for their handling and use. Further, it argues that qualified collections care staff and conservators from African museums should be involved in repatriation negotiations to enforce scientific testing of artifacts and establish safety measures for their handling and use before they are repatriated to Africa. The article also recommends that pesticide treatment information should accompany repatriated artifacts.Cet article traite de la question des contaminants potentiels issus de pesticides présents dans les artéfacts qui sont rapatriés par les musées des pays du Nord vers l'Afrique. Il souligne que la question de l'analyse scientifique des artéfacts pour détecter la présence des contaminants dangereux issus de pesticides est absente du discours sur le rapatriement dans les musées africains. Par conséquent, les protocoles de sécurité pour la manipulation et l'utilisation de ces artéfacts potentiellement contaminés n'ont pas été établis dans certains musées africains. Cette situation est aggravée par l'absence de législation imposant l'analyse des artéfacts et l'établissement de protocoles de sécurité pour y accéder. Cela expose le personnel des musées, les chercheurs et les autres visiteurs à des effets sur la santé causés par les produits chimiques toxiques présents dans les artéfacts. Dans ce contexte, l'article recommande que le rapatriement d'artéfacts dans les musées africains soit précédé d'analyses scientifiques des objets afin de déterminer la présence éventuelle de contaminants toxiques issus de pesticides et d'établir des protocoles de sécurité pour leur manipulation et leur utilisation. En outre, il plaide pour que le personnel qualifié chargé de l'entretien des collections et les conservateurs-restaurateurs des musées africains soient impliqués dans les négociations de rapatriement afin d'imposer des analyses scientifiques sur les objets et d'établir des mesures de sécurité pour leur manipulation et leur utilisation avant qu'ils ne soient rapatriés en Afrique. L'article recommande également que des informations relatives au traitement à l'aide de pesticides accompagnent les artéfacts rapatriés. Traduit par Anne-Stéphanie Etienne.Este artigo discute a questão dos potenciais contaminantes de agrotóxicos em artefatos que estão sendo repatriados por museus do hemisfério norte para a África. Ele destaca que a questão do teste científico de artefatos para contaminantes nocivos de pesticidas ausente do discurso de repatriação em museus africanos. Consequentemente, protocolos de segurança para manuseio e uso desses artefatos potencialmente contaminados não foram estabelecidos em alguns museus africanos. Isso é agravado pela falta de legislações que imponha testes dos artefatos e o estabelecimento de protocolos de segurança para acessá-los. Isso expõe a equipe do museu, pesquisadores e outros visitantes a problemas de saúde causados ⁣⁣por produtos químicos tóxicos nos artefatos. Em vista disso, o artigo recomenda que o repatriamento de artefatos para museus africanos seja precedido por testes científicos para determinar os possíveis contaminantes de pesticidas tóxicos neles presentes e estabelecer protocolos de segurança para seu manuseio e uso. Além disso, argumenta que a equipe técnica de cuidados de coleções e os conservadores de museus africanos devem estar envolvidos nas negociações de repatriação para impor testes científicos dos artefatos e estabelecer medidas de segurança para seu manuseio e uso antes de serem repatriados para a África. O artigo também recomenda que as informações sobre o tratamento de pesticidas acompanhem os artefatos repatriados. Traduzido por Beatriz Haspo.Este artículo analiza el tema de los posibles contaminantes con pesticidas en artefactos que están siendo repatriados por museos del norte global al África. Destaca que el tema de las pruebas científicas de artefactos para encontrar contaminantes de pesticidas nocivos no existeen el discurso de repatriación a los museos africanos. Por consiguiente, no se han establecido protocolos de seguridad para el manejo y uso de estos artefactos potencialmente contaminados en algunos museos africanos. Esto se ve agravado por la falta de legislación que obligue a hacer las pruebas en los artefactos y el desarrollo de protocolos de seguridad para acceder a ellos. Esto expone al personal del museo, a los investigadores y a otros visitantes a los efectos nocivos para la salud causados ⁣⁣por las sustancias químicas tóxicas en los artefactos. En vista de esto, este artículo recomienda que la repatriación de artefactos a museos africanos debe estar precedida por pruebas científicas en los artefactos para determinar los posibles contaminantes tóxicos de pesticidas en ellos y establecer protocolos de seguridad para su manejo y uso. Además, argumenta que el personal calificado para el cuidado de las colecciones y los conservadores de los museos africanos deben participar en las negociaciones de repatriación para hacer cumplir las pruebas científicas en los artefactos y establecer medidas de seguridad para su manejo y uso antes de que sean repatriados al África. El artículo también recomienda que la información sobre el tratamiento con pesticidas acompañe a los artefactos repatriados. Traducción: Amparo Rueda.This article is part of a Ph.D. thesis titled "Collections Conservation Practices and Possibilities of Contamination by Hazardous Pesticides: Towards a Non-Pesticide Approach of Conserving Organic Collections at the Natural History Museum of Zimbabwe. (https://repository.up.ac.za/handle/2263/89320)The University of Pretoria.https://www.tandfonline.com/journals/YJAC2024-04-12hj2023Visual Art

Re-dating of Chinese celadon sherds excavated on Mapungubwe Hill, a 13th Century Iron Age site in South Africa, using Raman spectroscopy, XRF and XRD

Chinese celadon shards of the Longquan type, believed to date from the Southern Song dynasty (1127-1279 AD), were excavated in 1934 on Mapungubwe Hill, a 13th century Iron Age site in the Limpopo valley, South Africa. We studied the shards with Raman spectroscopy, X-ray fluorescence spectroscopy (XRF) and X-ray diffractometry (XRD). The Raman polymerization index (Ip), calculated from the spectra of the glaze of the shards, indicated a higher firing temperature than expected for the relatively calcium rich Longquan glazes of the Southern Song dynasty. XRF analysis of the glaze and XRD measurements of the bulk of the shards supported this view and dates the shards to possibly the Yuan (1279-1368 AD) or even early Ming (1368-1644 AD) dynasties. These results have an impact on the chronology of the history of the region and therefore call for further research of a comparative nature of other Chinese celadon shards excavated on archaeological sites in Africa, as well as additional carbon dates of Mapungubwe hill.www.interscience.wiley.co

Conservation Science Education Online (CSEO) – A heritage science resource

Conservation Science Education Online (CSEO) is a new online resource that shares strategies for teaching science in art conservation and related cultural heritage fields. An overview will be given of how undergraduate chemistry curricula in the United States have used examples from cultural heritage. The field of art conservation will then be described with an emphasis on the science curricula taught in art conservation programs around the world. Challenges include relating theoretical learning to real-world applications and teaching scientific terminology and concepts to students who may have limited science backgrounds; as well, there is a lack of textbooks and resources with appropriate case studies. The newly launched CSEO online resource offers freely available, effective teaching methods in the form of modules developed by international educators in the field. The inaugural CSEO Conference 2022 served as an introduction to the online resource for a global audience and was the first dedicated conference to bring together heritage science educators to discuss challenges and teaching strategies with the goal of building such a resource. The conference facilitated discussions among participants about teaching strategies, with the intention that these topics would become modules for the online resource, available to all science educators