Nineteenth-and 20th-century glass was used in buildings in a variety of surprising and innovative... more Nineteenth-and 20th-century glass was used in buildings in a variety of surprising and innovative ways. Engineers (e.g., Gustave Falconnier), architects, and designers (e.g., Frank Lloyd Wright) applied known theories of light re-fraction to guarantee maximum light while guarding pri-vacy in an environment in which growing cities required radical solutions to the problem of lighting storefronts and sidewalks. The idea of using light refraction was translated into the use of glass prisms and glass bricks, which refract light into previously unlightable spaces, particularly those in deep courts and wells or on narrow streets bordered by tall buildings. The light refracted through the application of these glass elements brings natural light into factories, homes, and offices. These glass elements are now over a century old, and they are disappearing evidence of a time in which these architectural glass elements were more often used and more varied than similar elements are today. The d...
Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada, 2014
An alternative focused ion beam preparation method is used for sampling historical photographs co... more An alternative focused ion beam preparation method is used for sampling historical photographs containing metallic nanoparticles in a polymer matrix. We use the preparation steps of classical ultra-microtomy with an alternative final sectioning with a focused ion beam. Transmission electron microscopy techniques show that the lamella has a uniform thickness, which is an important factor for analytical transmission electron microscopy. Furthermore, the method maintains the spatial distribution of nanoparticles in the soft matrix. The results are compared with traditional preparation techniques such as ultra-microtomy and classical focused ion beam milling.
ABSTRACT During the conservation of two stained glass windows by Jan de Caumont at the Abbey ’t P... more ABSTRACT During the conservation of two stained glass windows by Jan de Caumont at the Abbey ’t Park (Heverlee, Leuven, Belgium) small fragments were removed from eight panes for analysis. Electron microscopy with energy dispersive X-ray sprectroscopy (SEM-EDX) was used to study the microstructure of several materials in these windows, and to perform quantitative analysis of the homogeneous materials. According to the SEM-EDX analyses, the glass appeared to be homogeneous. The deteriorated regions found in the fragments contained cracks, have a fractal appearance with stratifications of 2 µm in width and contained small islands of original unleached glass. Unfortunately, SEM-EDX did not allow a reliable chemical analysis of the different stratified layers due to the limitation in lateral resolution. The vitreous paint layer on one of the fragments consisted of lead glass surrounding many SiO2 and Fe2O3 particles. The green-blue and blue enamel paint layers were made with a low-melting SiO2-K2O-PbO glass. The colouring substance for the green-blue enamel paint layer was brass (i.e. an alloy of Cu and Zn), while for the blue enamel paint layer a substance known as saffre (a roasted sulphide ore rich in cobalt) was used. The compositions of the window glass fragments were all similar and consisted of high lime–low alkali (HLLA) glass (SiO2-K2O-CaO).
The I9th century saw the laying of the foundations of contemporary monument conservation. The deb... more The I9th century saw the laying of the foundations of contemporary monument conservation. The debate arose around preserving and restoring patrimony, and words were put into action. Two important parties, each with their own views, opposed each other in the story ...
This paper reports the successful characterisation of polymersfrom past conservation treatments u... more This paper reports the successful characterisation of polymersfrom past conservation treatments using Raman spectroscopywith a fibre-optic probe. It has been demonstratedfor the first time that this methodology is well suited to thein-situ examination of polymers used as adhesives and gapfillersfor conservation of glass artefacts. By means of aRaman spectroscopic instrument with a fibre-optic probe,conservation polymer spectra were recorded non-destructively,with a spectral resolution of 2 cm-1 in the range 200-3200 cm-1. Polymer identification proved straightforward forgap-fillers and, for adhesives, different polymers were alsosuccessfully distinguished, even in a glass / adhesive /glass bond less than 100 μm in width. In addition to polymeridentification, Fe2O3 was identified as the pigment not onlyin restored areas but also in the original grisaille paint forthe grey toning for the glass pictorial scene.
In 2008, Museum M in Louvain (Flanders, Belgium) acquired a panel depicting The Anointing at Beth... more In 2008, Museum M in Louvain (Flanders, Belgium) acquired a panel depicting The Anointing at Bethany that is believed once to have adorned the citys former Charterhouse. The panel required conservation treatment, which was preceded by a thorough art-historical and technical examination. It emerged that comparable panels are kept at the Metropolitan Museum of Art and the Riverside Church in New York. Chemical analyses show most of the glass in the panel to have a typical 16th century high-limelow-alkali composition. The conservation treatment was based on the evaluation of these findings and focused very strongly on enhancing the aesthetic balance for an improved reading of the panel.
In de eerste helft van de zestiende eeuw ontgroeide de Leuvense schilderkunst de laatgotische tra... more In de eerste helft van de zestiende eeuw ontgroeide de Leuvense schilderkunst de laatgotische traditie van Dieric Bouts en sloeg ze resoluut de weg in van de renaissance. Een sleutelrol in die ontwikkeling was weggelegd voor een kunstenaar met een neus voor vernieuwing, die zijn werken signeerde met het monogram IANR. De ware identiteit van deze veelzijdige figuur kwam pas kort geleden aan het licht: Jan Rombouts (ca. 1475/85-1535) maakte behalve schilderijen ook tekeningen en prenten en was actief als ontwerper en schilder van glasramen. In de tentoonstelling en catalogus 'Getekend, Jan R.' wordt zo goed als het volledige oeuvre van deze herontdekte renaissancekunstenaar voor het eerst bijeengebracht en geconfronteerd met werk van lokale en internationale tijdgenoten als Albrecht Bouts, Lucas van Leyden en Albrecht Dürer.
Spectrochimica Acta Part B: Atomic Spectroscopy, 2014
ABSTRACT The most unique and only known 16th century Antwerp majolica tile floor in Belgium is si... more ABSTRACT The most unique and only known 16th century Antwerp majolica tile floor in Belgium is situated in a tower of the Rameyenhof castle (Gestel, Belgium). This exceptional work of art has recently been investigated in situ by using X-ray fluorescence (XRF) and Raman spectroscopy in order to study the material characteristics. This study reports on the result of the analyses based on the novel combination of non-destructive and portable instrumentation, including a handheld XRF spectrometer for obtaining elemental information and a mobile Raman spectrometer for retrieving structural and molecular information on the floor tiles in the Rameyenhof castle and on a second, similar medallion, which is stored in the Rubens House museum in Antwerp (Belgium). The investigated material, majolica, is a type of ceramic, which fascinated many people and potters throughout history by its beauty and colourful appearance.
Nineteenth-and 20th-century glass was used in buildings in a variety of surprising and innovative... more Nineteenth-and 20th-century glass was used in buildings in a variety of surprising and innovative ways. Engineers (e.g., Gustave Falconnier), architects, and designers (e.g., Frank Lloyd Wright) applied known theories of light re-fraction to guarantee maximum light while guarding pri-vacy in an environment in which growing cities required radical solutions to the problem of lighting storefronts and sidewalks. The idea of using light refraction was translated into the use of glass prisms and glass bricks, which refract light into previously unlightable spaces, particularly those in deep courts and wells or on narrow streets bordered by tall buildings. The light refracted through the application of these glass elements brings natural light into factories, homes, and offices. These glass elements are now over a century old, and they are disappearing evidence of a time in which these architectural glass elements were more often used and more varied than similar elements are today. The d...
Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada, 2014
An alternative focused ion beam preparation method is used for sampling historical photographs co... more An alternative focused ion beam preparation method is used for sampling historical photographs containing metallic nanoparticles in a polymer matrix. We use the preparation steps of classical ultra-microtomy with an alternative final sectioning with a focused ion beam. Transmission electron microscopy techniques show that the lamella has a uniform thickness, which is an important factor for analytical transmission electron microscopy. Furthermore, the method maintains the spatial distribution of nanoparticles in the soft matrix. The results are compared with traditional preparation techniques such as ultra-microtomy and classical focused ion beam milling.
ABSTRACT During the conservation of two stained glass windows by Jan de Caumont at the Abbey ’t P... more ABSTRACT During the conservation of two stained glass windows by Jan de Caumont at the Abbey ’t Park (Heverlee, Leuven, Belgium) small fragments were removed from eight panes for analysis. Electron microscopy with energy dispersive X-ray sprectroscopy (SEM-EDX) was used to study the microstructure of several materials in these windows, and to perform quantitative analysis of the homogeneous materials. According to the SEM-EDX analyses, the glass appeared to be homogeneous. The deteriorated regions found in the fragments contained cracks, have a fractal appearance with stratifications of 2 µm in width and contained small islands of original unleached glass. Unfortunately, SEM-EDX did not allow a reliable chemical analysis of the different stratified layers due to the limitation in lateral resolution. The vitreous paint layer on one of the fragments consisted of lead glass surrounding many SiO2 and Fe2O3 particles. The green-blue and blue enamel paint layers were made with a low-melting SiO2-K2O-PbO glass. The colouring substance for the green-blue enamel paint layer was brass (i.e. an alloy of Cu and Zn), while for the blue enamel paint layer a substance known as saffre (a roasted sulphide ore rich in cobalt) was used. The compositions of the window glass fragments were all similar and consisted of high lime–low alkali (HLLA) glass (SiO2-K2O-CaO).
The I9th century saw the laying of the foundations of contemporary monument conservation. The deb... more The I9th century saw the laying of the foundations of contemporary monument conservation. The debate arose around preserving and restoring patrimony, and words were put into action. Two important parties, each with their own views, opposed each other in the story ...
This paper reports the successful characterisation of polymersfrom past conservation treatments u... more This paper reports the successful characterisation of polymersfrom past conservation treatments using Raman spectroscopywith a fibre-optic probe. It has been demonstratedfor the first time that this methodology is well suited to thein-situ examination of polymers used as adhesives and gapfillersfor conservation of glass artefacts. By means of aRaman spectroscopic instrument with a fibre-optic probe,conservation polymer spectra were recorded non-destructively,with a spectral resolution of 2 cm-1 in the range 200-3200 cm-1. Polymer identification proved straightforward forgap-fillers and, for adhesives, different polymers were alsosuccessfully distinguished, even in a glass / adhesive /glass bond less than 100 μm in width. In addition to polymeridentification, Fe2O3 was identified as the pigment not onlyin restored areas but also in the original grisaille paint forthe grey toning for the glass pictorial scene.
In 2008, Museum M in Louvain (Flanders, Belgium) acquired a panel depicting The Anointing at Beth... more In 2008, Museum M in Louvain (Flanders, Belgium) acquired a panel depicting The Anointing at Bethany that is believed once to have adorned the citys former Charterhouse. The panel required conservation treatment, which was preceded by a thorough art-historical and technical examination. It emerged that comparable panels are kept at the Metropolitan Museum of Art and the Riverside Church in New York. Chemical analyses show most of the glass in the panel to have a typical 16th century high-limelow-alkali composition. The conservation treatment was based on the evaluation of these findings and focused very strongly on enhancing the aesthetic balance for an improved reading of the panel.
In de eerste helft van de zestiende eeuw ontgroeide de Leuvense schilderkunst de laatgotische tra... more In de eerste helft van de zestiende eeuw ontgroeide de Leuvense schilderkunst de laatgotische traditie van Dieric Bouts en sloeg ze resoluut de weg in van de renaissance. Een sleutelrol in die ontwikkeling was weggelegd voor een kunstenaar met een neus voor vernieuwing, die zijn werken signeerde met het monogram IANR. De ware identiteit van deze veelzijdige figuur kwam pas kort geleden aan het licht: Jan Rombouts (ca. 1475/85-1535) maakte behalve schilderijen ook tekeningen en prenten en was actief als ontwerper en schilder van glasramen. In de tentoonstelling en catalogus 'Getekend, Jan R.' wordt zo goed als het volledige oeuvre van deze herontdekte renaissancekunstenaar voor het eerst bijeengebracht en geconfronteerd met werk van lokale en internationale tijdgenoten als Albrecht Bouts, Lucas van Leyden en Albrecht Dürer.
Spectrochimica Acta Part B: Atomic Spectroscopy, 2014
ABSTRACT The most unique and only known 16th century Antwerp majolica tile floor in Belgium is si... more ABSTRACT The most unique and only known 16th century Antwerp majolica tile floor in Belgium is situated in a tower of the Rameyenhof castle (Gestel, Belgium). This exceptional work of art has recently been investigated in situ by using X-ray fluorescence (XRF) and Raman spectroscopy in order to study the material characteristics. This study reports on the result of the analyses based on the novel combination of non-destructive and portable instrumentation, including a handheld XRF spectrometer for obtaining elemental information and a mobile Raman spectrometer for retrieving structural and molecular information on the floor tiles in the Rameyenhof castle and on a second, similar medallion, which is stored in the Rubens House museum in Antwerp (Belgium). The investigated material, majolica, is a type of ceramic, which fascinated many people and potters throughout history by its beauty and colourful appearance.
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