Tag: Conservation

Unusual compound found in Rembrandt’s The Night Watch

Unusual compound found in Rembrandt’s The Night Watch

An international team of scientists from the Rijksmuseum, the CNRS, the ESRF the European Synchrotron, the University of Amsterdam and the University of Antwerp, have discovered a rare lead compound (named lead formate) in Rembrandt’s masterpiece The Night Watch. This discovery, which is a first in the history of the scientific study of paintings, provides new insight into 17th-century painting technique and the conservation history of the masterpiece. The study is published in Angewandte Chemie – International edition.

The Night Watch, painted in 1642 and displayed today in the Rijksmuseum Amsterdam (The Netherlands), is one of Rembrandt’s most important masterpieces and largest work of art. In the framework of the 2019 Operation Night Watch, the largest research and conservation project ever undertaken for Rembrandt’s masterpiece, an international research team joined forces to study how the painting materials react chemically and with time.

The team of scientists combined multi-scale imaging methods in order to chemically study the materials used by Rembrandt in The Night Watch. A X-ray scanning instrument developed at the University of Antwerp (Belgium) was applied directly to the painting, while tiny fragments taken from the painting were studied with synchrotron micro X-ray probes, at the ESRF, the European Synchrotron (France), and PETRA-III facility (Germany). These two types of analyses revealed the presence of an unexpected organo-metallic compound: lead formates. This compound had never been detected before in historic paintings: “In paintings, lead formates have only been reported once in 2020, but in model paintings (mock-up, fresh paints). And there lies the surprise: not only do we discover lead formates, but we identify them in areas where there is no lead pigment, white, yellow. We think that probably they disappear fast, this is why they were not detected in old master paintings until now”, explains Victor Gonzalez, CNRS researcher at the Supramolecular and Macromolecular Photophysics and Photochemistry (PPSM) laboratory (CNRS/ENS Paris-Saclay) and first author of the paper.

Read more on the ESRF website

Image: The Night Watch, Rembrandt van Rijn, 1642

Credit: Rijskmuseum Amsterdam

From conservator to researcher at the world’s brightest synchrotron

From conservator to researcher at the world’s brightest synchrotron

Light sources around the world are playing an increasingly important role in helping to uncover the past and protect historical objects for generations to come. Ida Fazlić is currently a PhD student at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. Her research is focusing on the use of metal catalysts that are used to speed up the drying reactions of historical and industrial paints. Ida’s project will provide valuable information to collaborator Rijksmuseum on the use or misuse of dryers throughout history and up to the current day. Also there effect on the stability and aesthetic of the painted objects.

Ida was attracted to this area of work through her valuable experience of working as a conservator and restorer at the national gallery of Bosnia and Herzegovina. This work led her to question the chemical and physical processes that caused the degradation of the painted layers that she was seeing on a daily basis. Ida decided to study the crucial and very important role of science and technology in conservation of cultural heritage objects. For Ida, the best thing about working at a light source is that, “You have endless opportunities of going as far in your research as you want to go and in any direction that you want to go because at any moment you have the world’s most powerful material investigation techniques at hand.”

Conservation boost for 500-year-old shipwreck

Conservation boost for 500-year-old shipwreck

The ESRF has allowed scientists to discover nanoparticles that could lead to degradation in a 500-year-old shipwreck: the Mary Rose, an English warship.

Almost 40 years ago, a salvage operation brought to the surface the Mary Rose warship, which used to be Henry VIII’s favourite warship and sank in 1545. Throughout these years, scientists have been using conservation treatments to preserve it. Unfortunately, the remains of the ship are vulnerable to degradation after spending more than 400 years at the bottom of the sea, where harmful deposits collected inside the ship’s wooden hull.

A team of researchers, led by the University of Sheffield, has used ctPDF, an x-ray technique developed at the European Synchrotron Radiation Facility (ESRF) and Columbia University, to obtain vital information on the nanostructure of substances lodged within the ship’s wood and that could lead to the Mary Rose degrading. 

Researchers were previously unable to obtain information on the nature and structure of these deposits, as they are incredibly diverse and exist on such a small scale. The fragility of the remains also hindered efforts to find out more about the substances.

ctPDF has enabled researchers to identify the harmful deposits for the first time and in a non-destructive way. Serena Cussen, Chair in Functional Nanomaterials at the University of Sheffield and corresponding author of the publication, explains: “This project has brought together researchers from around the world to uncover the nature of potentially harmful deposits lodged within the wooden hull of the Mary Rose. These deposits, when exposed to air, can act to degrade the wood. By understanding their structure, we might understand better these degradation pathways, as well as develop treatments that target their removal”.

Read more on the ESRF website

Image: The hull of the Mary Rose

Credit: The Mary Rose Trust

Conserving Rita Letendre’s famous artworks

Conserving Rita Letendre’s famous artworks

Research undertaken at the Canadian Light Source (CLS) at the University of Saskatchewan was key to understanding how to conserve experimental oil paintings by Rita Letendre, one of Canada’s most respected living abstract artists.

The work done at the CLS was part of a collaborative research project between the Art Gallery of Ontario (AGO) and the Canadian Conservation Institute (CCI) that came out of a recent retrospective Rita Letendre: Fire & Light at the AGO. During close examination, Meaghan Monaghan, paintings conservator from the Michael and Sonja Koerner Centre for Conservation, observed that several of Letendre’s oil paintings from the fifties and sixties had suffered significant degradation, most prominently, uneven gloss and patchiness, snowy crystalline structures coating the surface known as efflorescence, and cracking and lifting of the paint in several areas.

Read more on the Canadian Light Source website

Image: Rita Letendre. Victoire [Victory], 1961. Oil on canvas, Overall: 202.6 × 268 cm. Art Gallery of Ontario. Gift of Jessie and Percy Waxer, 1974, donated by the Ontario Heritage Foundation, 1988. © Rita Letendre L74.8.

Saving Rembrandt for future generations

Saving Rembrandt for future generations

New research on beamline I18 at Diamond Light Source investigates preservation techniques for Old Master paintings.

The surface of many Old Master paintings has been affected by the appearance of whitish lead-rich deposits, which are often difficult to fully characterise, thereby hindering conservation. Painted in 1663, Rembrandt’s Homer is an incredibly valuable and much-loved painting. Like many Old Masters it has a long and eventful past, which has taken its toll on the painting’s chemistry. The test of time and environmental factors, combined with the painting’s history, caused a barely visible, whitish crust to form on the surface of the painting. This crust indicates that chemical reactions are occurring which could potentially pose as risk for Homer and other old paintings if not kept in stable museum conditions.
A paper in ChemComm (Royal Society of Chemistry) has been published by a team of conservation scientists from the Mauritshuis in the Hague and the Rijksmuseum in Amsterdam, University of Amsterdam and scientists from Finden Ltd, UCL and Diamond Light Source, the UK’s National Synchrotron. Called “Unravelling the spatial dependency of the complex solid-state chemistry of Pb in a paint micro-sample from Rembrandt’s Homer using XRD-CT,” this paper is particularly timely given the celebrations occurring in 2019 to mark 350 years since the death of Rembrandt and the Dutch Golden Age. A paint micro-sample from Rembrandt’s Homer was imaged using X-ray Diffraction Computed Tomography (XRD-CT) in order to understand the evolving solid-state Pb chemistry from the painting surface and beneath.

>Read more on the Diamond Light Source website

Image: Stephen Price, Lead author from Diamond Light Source and Finden Ltd.

The secret to Rembrandt’s impasto unveiled

The secret to Rembrandt’s impasto unveiled

Rembrandt van Rijn revolutionized painting with a 3D effect using his impasto technique, where thick paint makes a masterpiece protrude from the surface. Thanks to the ESRF, three centuries later an international team of scientists led by the Materials Science and Engineering Department of TU Delft and the Rijksmuseum have found how he did it.

Impasto is thick paint laid on the canvas in an amount that makes it stand from the surface. The relief of impasto increases the perceptibility of the paint by increasing its light-reflecting textural properties. Scientists know that Rembrandt, epitome of the Dutch Golden Age, achieved the impasto effect by using materials traditionally available on the 17thcentury Dutch colour market, namely lead white pigment (a mixture of hydrocerussite Pb3(CO3)2.(OH)2 and cerussite PbCO3), and organic mediums (mainly linseed oil). The precise recipe was, however, unknown until today.

>Read more on the European Synchrotron (ESRF) website

Image: Scientist Marine Cotte on beamline ID21.
Credit: Steph Candé.

Research on ancient teeth reveals complexity of human evolution

Research on ancient teeth reveals complexity of human evolution

Fossil records enable a detailed reconstruction of our planet’s history and of the evolution of our species. In particular, teeth are a sort of biological archive that record in their structures (enamel, dentine and pulp chamber) the different phases of the human evolution. An international team of researchers led by Clément Zanolli from the Université Toulouse III Paul Sabatier (France) has characterized human dental remains from Fontana Ranuccio (Latium) and Visogliano (Friuli-Venezia Giulia), Italy through a comparative high-resolution endostructural analysis based on microfocus X-ray microtomography (mCT) scanning and detailed morphological analyses. We examined the shape and arrangement of tooth tissues (see Fig. 1) and compared them with teeth of other human species (see Fig. 2).

With an age of around 450,000 years before present, the analysed dental remains from the sites of Fontana Ranuccio, located 50 km south-east of Rome, and Visogliano, located 18 km north-west of Trieste, are part of a very short list of fossil human remains from Middle Pleistocene Europe and are among the oldest human remains on the Italian Peninsula.
From the data obtained through X-ray μ-CT measurements performed at the TomoLab station of Elettra and at the Multidisciplinary Laboratory of the ‘Abdus Salam’ International Centre for Theoretical Physics in Trieste (Italy), we found that the teeth of both sites share similarities with Neanderthals but they are distinct from modern humans. This study adds to an emerging picture of complex human evolution in Middle Pleistocene Eurasia.  The investigated fossil teeth show that Neanderthal dental features had evolved by around 450,000 years ago.

>Read more on the Elettra Sincrotrone Trieste website

Image: Volume rendering of the Fontana Ranuccio (FR1R and FR2) and Visogliano (Vis. 1-Vis. 6) tooth specimens. The enamel is represented in blue while the dentine in yellow. All specimens were imaged by X-ray μCT at the Tomolab station of Elettra and at the Multidisciplinary Laboratory of the ICTP.     
Credit:  doi: 10.1371/journal.pone.0189773

How did humans live 5000 years ago?

How did humans live 5000 years ago?

Researchers from the Cyprus Institute, in collaboration with the Iranian Center of Archaeological Research, have worked around the clock for a week on ID16A to discover more about the lifestyle of our ancestors.

How did people live 5000 years ago? What did they eat? What can we learn of their health? Were they exposed to contaminants? To answer these questions with various techniques researchers first need to understand more about the preservation state of ancient human hair. In order to do this, a team from Cyprus Institute is  scanning hair remains found within burials at the ancient site of Shahr-I-Sokhta, in Iran.
In this urban settlement, at a crossroads of important ancient trade routes that later became part of the Silk Road, there was busy commercial and manufacturing activity around metal and precious materials as evidenced by the  artifacts found onsite during archaeological excavations. Archaeologists have also found remains of the inhabitants of the city dating to the 3rd millennium BC, and their state of preservation is remarkable. “The climate in this area is very arid and hot, and this has led to preservation of body tissues not often found with human skeletons, including hair”, explains Kirsi Lorentz, assistant professor at the Cyprus Institute.

>Read more on the European Synchrotron (ESRF) website

Image: Aerial view of the Shahr-I-Sokhta site, in Iran.
Credit: Media Rahmani

Researchers provide new insights into fate of Franklin Expedition

Researchers provide new insights into fate of Franklin Expedition

Synchrotron studies of bone and teeth have led a multi-institution team of scientists to conclude that lead poisoning did not play a pivotal role in the deaths of crew members of the ill-fated Franklin Expedition of 1845, says a paper published today in the journal PLOS ONE.
“Our findings don’t mean the crew members weren’t exposed to high levels of lead, and they don’t mean the sailors weren’t impacted. But our findings don’t lend support to massive and sustained lead poisoning that would have compromised them any more than any sailor of that era would have been compromised,” said David Cooper of the University of Saskatchewan, an author of the paper.

Data collected by the team don’t support the theory that compromised physical and/or neurological health resulting from lead poisoning prompted the stranded sailors’ fatal march southward in April 1848 to try to reach a Hudson Bay Company post, said Cooper, Canada Research Chair in Synchrotron Bone Imaging in the Department of Anatomy, Physiology and Pharmacology at the U of S College of Medicine.
That theory arose from previous analyses of bone, hair and soft tissue samples from the frozen bodies of the sailors, which had found they had high levels of lead in their tissue.
The 11-member team includes Treena Swanston, who was a post-doctoral fellow on Cooper’s team at the U of S when the research began and is currently an assistant professor at MacEwan University. She is lead author of the paper.

>Read more on the Canadian Light Source website

Image: Sanjukta Choudhury (U of S), David Cooper (U of S), and Brian Bewer (CLS) at a CLS beamline.

Synchrotron researchers uncover lost images from the 19th century

Synchrotron researchers uncover lost images from the 19th century

Art curators will be able to recover images on daguerreotypes, the earliest form of photography that used silver plates, after scientists learned how to use light to see through degradation that has occurred over time.

Research published today in Scientific Reports includes two images from the National Gallery of Canada’s photography research unit that show photographs that were taken, perhaps as early as 1850, but were no longer visible because of tarnish and other damage. The retrieved images, one of a woman and the other of a man, were beyond recognition. “It’s somewhat haunting because they are anonymous and yet it is striking at the same time,” said Madalena Kozachuk, a PhD student in the Department of Chemistry at Western University and lead author of the scientific paper.

“The image is totally unexpected because you don’t see it on the plate at all. It’s hidden behind time. But then we see it and we can see such fine details: the eyes, the folds of the clothing, the detailed embroidered patterns of the table cloth.”
The identities of the woman and the man are not known. It’s possible that the plates were produced in the United States, but they could be from Europe.
For the past three years, Kozachuk and an interdisciplinary team of scientists have been exploring how to use synchrotron technology to learn more about chemical changes that damage daguerreotypes.

>Read more on the Canadian Light Source (CLS) website

Image: A mounted daguerreotype resting on the outside of the vacuum chamber within the SXRMB (a beamline at CLS) hutch.
Credit: Madalena Kozachuk.

Enlightening yellow in art

Enlightening yellow in art

Scientists from the University of Perugia (Italy), CNR (Italy), University of Antwerp, the ESRF and DESY, have discovered how masterpieces degrade over time in a new study with mock-up paints carried out at synchrotrons ESRF and DESY. Humidity, coupled with light, appear to be the culprits.

The Scream by Munch, Flowers in a blue vase by Van Gogh or Joy of Life by Matisse, all have something in common: their cadmium yellow pigment. Throughout the years, this colour has faded into a whitish tone and, in some instances, crusts of the paint have arisen, as well as changes in the morphological properties of the paint, such as flaking or crumbling. Conservators and researchers have come to the rescue though, and they are currently using synchrotron techniques to study in depth these sulphide pigments and to find a solution to preserve them in the long run.

“This research has allowed us to make some progress. However, it is very difficult for us to pinpoint to what causes the yellow to go white as we don’t have all the information about how or where the paintings have been kept since they were done in the 19th century”, explains Letizia Monico, scientist from the University of Perugia and the CNR-ISTM. Indeed, limited knowledge of the environmental conditions (e.g., humidity, light, temperature…) in which paintings were stored or displayed over extended periods of time and the heterogeneous chemical composition of paint layers (often rendered more complex by later restoration interventions) hamper a thorough understanding of the overall degradation process.

>Read more on the ESRF website

Image: Some of the mock-up paints, prepared by Letizia Monico. Credits: C. Argoud.

The enigma of Rembrandt’s vivid white

The enigma of Rembrandt’s vivid white

Some of Rembrandt’s masterpieces are at the ESRF for some days, albeit only in minuscule form. The goal: to unveil the secrets of the artist’s white pigment.

Seven medical students surround a dead body while they attentively look at how the doctor is dissecting the deceased. The scene is set in a dark and gloomy environment, where even the faces of the characters show a grey tinge. Strangely, the only light in the scene is that coming from their white collars and the white sheet that partially covers the body. The vivid white creates a perplexing light-reflecting effect. Welcome to painting The anatomy lesson of Dr. Nicolaes Tulp, a piece of art displaying the baffling technique of the impasto, of which Rembrandt, its author, was a master.

Impasto is thick paint laid on the canvas in an amount that makes it stand from the surface. The relief of impasto increases the perceptibility of the paint by increasing its light-reflecting textural properties. Scientists know that Rembrandt achieved the impasto effect by using materials traditionally available on the 17th century Dutch colour market, namely the lead white pigment (mix of hydrocerussite Pb3(CO3)2.(OH)2 and cerussite PbCO3), chalk (calcite CaCO3) and organic mediums (mainly linseed oil). The precise recipe he used is, however, still unknown.

>Read more on the European Synchrotron website

Image: The anatomy lesson of Dr. Nicolaes Tulp, by Rembrandt.

 

Megachirella -the mother of all lizards

Megachirella -the mother of all lizards

A new international research rewrites the history of reptiles starting from a fossil found in the Dolomites.

The origin of lizards and snakes should be pushed back by about 75 million years, as documented by a small reptile, Megachirella wachtleri, found almost 20 years ago in the Dolomites and rediscovered today thanks to cutting-edge techniques in the field of 3D analysis and the reconstruction of evolutionary relationships. Evidence to this effect has been provided by an international paleontological research with the participation of the MUSE Science Museum of Trento, in collaboration with the “Abdus Salam” International Centre of Theoretical Physics of Trieste, the Enrico Fermi Centre of Rome and Elettra Sincrotrone Trieste. The results have been published in the prestigious science journal Nature, which has also dedicated its cover image to research.

The international team has identified Megachirella wachtleri – a small reptile which lived approximately 240 million years ago in what are today the Dolomites – the most ancient lizard in the world thereby providing key insight into the evolution of modern lizards and snakes.
The data – obtained by 3D X-ray imaging techniques and the analysis of DNA sequences – suggest that the origin of “squamates”, i.e. the group comprising lizards and snakes,is older than previously thought and that it can be dated to approximately 250 million years ago, before the most extensive mass extinction in history.

>Read more on the Elettra Sincrotrone Trieste website
>Watch here a video about the scientific discovery

Image: Megachirellawandering amidst the lush vegetation that approximately 240 million years ago surrounded the dolomitic beaches.
Credit: Davide Bonadonna

 

Hidden medical text read for the first time in a thousand years

Hidden medical text read for the first time in a thousand years

With X-ray imaging at SLAC’s synchrotron, scientists uncovered a 6th century translation of a book by the Greek-Roman doctor Galen.

An influential physician and a philosopher of early Western medicine, Galen of Pergamon was the doctor of emperors and gladiators. One of his many works, “On the Mixtures and Powers of Simple Drugs,” was an important pharmaceutical text that would help educate fellow Greek-Roman doctors.

The text was translated during the 6th century into Syriac, a language that served as a bridge between Greek and Arabic and helped spread Galen’s ideas into the ancient Islamic world. But despite the physician’s fame, the most complete surviving version of the translated manuscript was erased and written over with hymns in the 11th century – a common practice at the time. These written-over documents are known as palimpsests.

An international team of researchers is getting a clear look at the hidden text of the Syriac Galen Palimpsest with an X-ray study at the Stanford Synchrotron Radiation Lightsource (SSRL) at the Department of Energy’s SLAC National Accelerator Laboratory.

>Read more on the Stanford Synchrotron Radiation Lightsource website

Image: Conservators at Stanford University Libraries removed the pages from the leather-bound cover of the book of hymns, and mounted each leaf in an individually fitted, archival mat. The individual mats were placed in an aluminum frame to secure the pages while examining the underlying text with X-rays at the Stanford Synchrotron Radiation Lightsource.
Credit: Farrin Abbott / SLAC National Accelerator Laboratory

Determining the impact of post-conservation corrosion

Determining the impact of post-conservation corrosion

When King Henry VIII’s flagship, the Mary Rose, sank off Portsmouth in 1545, it took with it 1248 iron cannonballs. Since the excavation of the shipwreck (from 1979-1983), the cannonballs have been conserved in different ways, offering a unique opportunity to study different conservation methods.

Humans have been using iron to make weapons, tools and ceremonial items for more than 20,000 years, but once these objects have been excavated they are at risk from corrosion, which can be accelerated in the presence of chlorine. Each recovered artefact has to be conserved to prevent it from deteriorating in the presence of air and water. Until now, a comparison of the effectiveness of different conservation methods has been hampered by the variable nature of both the artefacts found, and the environment in which they were buried.

>Read more on the Diamond Light Source website

Image: Dr Eleanor Schofield, Dr Giannantonio Cibin and Hayley Simon with iron shot and samples on Diamond’s B18 beamline.
Credit: Diamond Light Source

Technique provides insights into historic maritime artefact

Technique provides insights into historic maritime artefact

Recently an advanced X-ray imaging technique was used on a historic pewter plate linked to the early exploration of Australia by the Dutch in the 17th century. X-ray fluorescence (XRF) has proven to be a highly useful analytical tool for the study of cultural objects, such as works of art and artefacts.

“The non-destructive analysis can provide information about how the objects were made, their composition and insight for conservation strategies,” said XRF beamline scientist Dr Daryl Howard.
“The fast detector on the instrument and its high sensitivity allows us to keep the exposure to radiation to a minimum, which is important for rare and valuable objects. “

In December last year, a small group from the Rijksmuseum in Amsterdam and the Queen Victoria Museum and Art Gallery (QVMAG) in Tasmania brought the Hartog Plate to the Synchrotron for scanning.

>Read more on the Australian Synchrotron website

Image: (extract) X-ray fluorescence scan image showing elemental distribution of bismuth (red) lead (green) and germanium (blue). Entire picture here.