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Scientific analyses of the traditional materials and methods in thangka production are uncommon, as thangkas are sacred objects, the sampling of which is discouraged, in order to preserve their integrity. This study builds on this important ethical challenge and presents a three-stage methodology that systematically delves deeper into each layer of the composition, successfully enabling the investigation of different phases of production. In the first stage, visual examination of the painting, including observations under magnification, was used to assess its condition. In the next step, the infrared reflected (IRR) and short-wave infrared (SWIR) images revealed the underdrawing and instances of modifications as well as colour notations. Additionally, ultraviolet-induced visible luminescence (UVL), infrared-reflected false colour (IRRFC) and X-ray images provided important preliminary information on the colourants present, the nature of the underdrawing, and the painting technique. In the final stages, fibre optic reflectance (FORS), Fourier-transform infrared (FTIR) and Raman spectroscopies confirmed the identity of many of the pigments (cinnabar/vermillion, minium, iron oxide, malachite, azurite, indigo, Indian lac), the ground and the binder used for the blue and green paint layers. In addition, key details of practices and materials were revealed, that may indicate provenance or other information of scholarly importance. These will constitute a helpful comparison to existing and future studies of other thangkas.

The appraisal of the design and the weaving structure of Islamic knotted-pile carpets can tell plenty about the context in which they were produced, and the identification of signs of deterioration can help to establish their condition. These are often somewhat imprecise and laborious examinations, especially when considering carpets of large dimensions. Analytical methods that support these disciplines urge further exploration so that improved interpretations can be obtained. An interdisciplinary combination of art history, analytical science and textile conservation aimed, on the one hand, to improve the weaving examination of these complex textile objects – by considering the spin of threads and the ply of yarns; the knot count and density; and the weaving structure of warps, wefts and piles – and on the other, to help their condition assessment – by mapping of damaged areas, old repairs and contaminations. For this purpose, the possibilities and limitations of several non-invasive imaging techniques, namely transmitted, raking or incident visible, ultraviolet (UV) and infrared (IR) illumination through Visual Spectral Comparator (VSC), as well as conventional X-radiography, mammography and (micro) CT scanning, were assessed to support the conventional visual examination of the weaving details and present condition of two 17th-century Safavid knotted-pile carpet fragments. Observation with NUV and NIR imaging with VSC, as well as CT techniques, offered enriching overviews about weaving characteristics, damaged areas or contaminations that were not easily discernible with the naked eye, thus supporting the conventional visual examination. As a result, detailed digital mappings about the technological structure and the condition of the fragments could be obtained in a relatively efficient and accessible way. Moreover, combining art historical identification of the design with the analysis of the weaving structure confirmed that both carpet fragments are border corners that originally belonged to much larger carpets made in the so-called “Indo-Persian” style. The outcome of this interdisciplinary research brings very useful contributions for future art historical and conservation assessments of historical carpets, and it encourages further exploration of imaging techniques in the examination of other textile objects in museums and private collections.

The Foundation of the American Institute for Conservation oral history archive, which began in 1975, contains almost 300 interviews with pioneer conservators, conservation scientists, and art historians. Technical examination and technical art history, as exemplified by Roger H. Marijnissen’s publications, has undergone many changes since the 1950s; this article briefly surveys the field, focusing on the examination of easel paintings, with the aid of voices and personal observations from the interviews available in the international oral history archive of the Foundation of the American Institute for Conservation. La Fondation de l'Institut américain de Conservation pour les archives de la tradition orale (Foundation of American Institute for Conservation - oral history archive), qui a débuté ses travaux en 1975, rassemble près de 300 entretiens avec des conservateurs pionniers, des scientifiques de la conservation et des historiens de l'art. Examens techniques et histoire de l'art technique, comme donnés en exemple par Roger H. Marijnissen dans ses publications, ont subi beaucoup de changements depuis les années 1950; cet article examine brièvement ce champ, se concentrant sur l'examen de peintures de chevalet, par le biais des observations personnelles et des entretiens disponibles dans les Archives de Tradition orale internationales de la Fondation de l'Institut américain pour la Conservation.

Une sculpture représentant une pomme réalisée par collage de l’artiste tchèque Jiří Kolář et datant de 1972, a été soumise à un traitement de conservation-restauration. La sculpture présentait des dommages structurels causés par des facteurs externes ainsi que des surfaces encrassées. Les interrogations déontologiques soulevées lors de la restauration d’une œuvre d’art contemporain ont représenté un aspect important de l’étude. Par conséquent, la majeure partie des recherches a été dévolue à la compréhension du matériau et de la structure, celle des intentions de l’artiste,tout comme du concept et de la signification de l’œuvre. Ce travail a été étayé par une recherche scientifique ayant pour but d’évaluer l’efficacité du Triammonium citrate comme agent de nettoyage à base aqueuse, ainsi que par une analyse de la construction en trois dimensions de l’œuvre d’art.A collaged sculpture of an apple by the Czech artist Jiří Kolář, dated 1972 was presented for conservation. The sculpture suffered from structural damage caused by external factors and ingrained surface dirt. The ethical implications raised in conserving a contemporary artwork were an important aspect and subsequently an understanding of the materials and structure, the artist’s intentions, concept and meaning of the artwork formed a large part of the research. Combined with this was scientific research into the effectiveness of Tri-ammonium Citrate as an aqueous surface cleaning agent and analysing construction of 3-Dimensional artworks.