Julio M del Hoyo-Meléndez

• PhD
• Head of Laboratory at The National Museum in Krakow

This paper summarizes the results of a study conducted on historical samples of metal threads and lamellas from laces used for the decoration of textile garments, currently housed at the National Museum in Kraków. The items date from the 17th to the 19th century and were produced in Central and Western Europe. A total of 477 samples obtained from 1...

This article explores the performance and capabilities of a custom-developed full-field XRF imaging spectrometer operating at limited energy resolution (1.1 keV FWHM at 5.9 keV) for elemental mapping of three-dimensional (3D) objects. The measurements performed involved two, different in spatial depth, historical artworks from the collection of the...

Obiektem badań była rzeźba z drewna lipowego przedstawiająca Madonnę z Dzieciątkiem (120 × 55 × 38 cm) pochodząca z klasztoru Dominikanów w Krakowie. Figura została wykonana w pierwszej ćwierci XVI wieku przez rzeźbiarza znającego dzieła powstałe w warsztacie Wita Stwosza w Norymberdze, na co wskazuje charakterystyczny dla dzieł tego mistrza układ...

Understanding the chemistry of dyes and pigments found in cultural heritage objects and their permanence is central for their preservation. Heritage science research has generally focused on either identification of materials present on actual objects or accelerated and natural ageing of mock‐up samples prepared using historically accurate methods...

The multidisciplinary, noninvasive analysis of baroque amber artworks is part of a research project that deals with the most valuable objects from the Museum of Gdansk (Poland). The two most interesting objects will be presented here: a Baroque Gdansk wardrobe‐shaped amber cabinet (made by Johann Georg Zernebach, Gdansk, 1724) and a crucifix (Gdans...

The study explores drawing materials from the 17th century to the present using noninvasive techniques like Raman spectroscopy in selected cases supplemented by x‐ray fluorescence (XRF) spectroscopy. This publication is an effort to expand knowledge across diverse periods and materials. A collection of six drawings spanning from 1700 to 1899 from t...

Amber has been used to create decorative items for centuries, but its degradation presents challenges for conservators. This study identifies substances historically used to protect amber objects, especially those from 17th and 18th century Gdansk workshops. Despite their historical value, information on amber conservation is scarce. Traditional su...

The Lady with an Ermine is one of the greatest masterpieces by the Italian artist Leonardo da Vinci from around 1489-1490, depicting Cecilia Gallerani, most likely at the time when she was the mistress of Ludovico Sforza, Duke of Milan. This painting belongs to a group of four portraits of women painted by Leonardo along with the Mona Lisa, Ginevra...

This study focuses on the analysis of Japanese woodblock prints from the Taisho period, specifically copies of renowned artists such as U. Hiroshige, recently donated to the Far Eastern Art Department of the National Museum in Kraków by Jens Wiebel. The aim of this research is to investigate the paper production methods employed for these woodblock...

Artefacts made of and from untypical materialswith the use of sophisticated techniques preserved in museumsconstitute an exceptional challenge to museum curators. Suchis the case of two letters described in the paper, written onbirch bark by someone signed as the female: Janka and Jaśkadispatched to her mother from the Soviet Polovinka Gulag inthe...

This paper presents a statistical approach for the compositional study and classification of 213 coins from medieval Poland. Radiation techniques, such as X-ray fluorescence (XRF) and neutron activation analysis (NAA), which operate in the X-ray (0.001–5 × 10−8 m) and neutron (2–40 × 10−10 m) wavelength ranges, respectively, have demonstrated their...

Near-surface analytical techniques, such as X-ray fluorescence (XRF), high energy particle induced X-ray emission (PIXE) as well as particle induced gamma-ray emission (HE-PIGE) and neutron activation analysis (NAA), which provide an analytical data from greater depths, have been used to study more than two hundred medieval denars of the Piast dyna...

Artykuł omawia prace konserwatorskie oraz technikę wykonania dwóch jedwabnych dwustronnie malowanych chorągwi ze zbiorów Muzeum Narodowego w Krakowie: szesnastowiecznej chorągwi województwa poznańskiego lub mazowieckiego, nr inw. MNK-XIV-882, oraz osiemnastowiecznej chorągwi gwardii Stanisława Poniatowskiego Króla Polskiego, nr inw. MNK-XIV-883. Ch...

Museum collections are constantly expanded to include plastic-based materials. Taking into account the dynamic development of polymer chemistry, presumably in the nearest years, the number of museum objects made of plastic continues to grow. Contrary to popular opinions, items made of plastic are not very durable, and they are easily susceptible to...

The chosen object from the National Museum in Kraków collection (the Amber Altar of the Lord’s Passion) was examined by Raman spectroscopy (RS) and reflectance imaging spectroscopy (RIS) in short wavelength infrared (SWIR) spectral range. These studies allowed to identify the type of amber used and to assess the existence of a degraded layer. Based...

A multi-disciplinary project focusing on the non-invasive analysis of the early painting of Sofonisba Anguissola (1532–1625), “Self-portrait at an Easel” (Museum-Castle in Łańcut, Poland) was implemented out applying macro- and micro-analytical techniques. Technical photography using UV radiation and X-radiography were used along with macro-XRF to...

A multidisciplinary investigation was conducted on the painting Judith with the Head of Holofernes from about 1530, attributed to Lucas Cranach the Elder. The investigation started with a digital imaging approach using several techniques in the UV–VIS-IR range, as well as X-radiography. The imaging approach was combined with physico-chemical charac...

An electrochemical study was conducted on a series of samples taken from the metal supports of ten coffin portraits and one funeral portrait from the collection of the National Museum in Krakow (Poland) as a part of a research project aimed to their study and preservation. An approach that makes use of voltammetry of immobilized particles (VIMP) me...

Lighting is a critical component in a museum environment because, together with temperature, relative humidity and pollutants, it is one of the damaging factors able to produce long‐term, cumulative and irreversible photodegradation processes. To correctly preserve artworks, limiting illuminance and exposure is recommended, allowing on one side the...

Microfading testing allows to evaluate the sensitivity to light of a specific artwork. Characterization of the illumination spot is important to determine its shape, dimensions, light distribution, and intensity in order to limit and account for possible damage. In this research the advantages and disadvantages of several methods used to determine...

Microfading testers have become widely accepted by the conservation science community for establishing and recommending appropriate lighting conditions that minimize damage to collections. These devices offer the opportunity of measuring the photostability of cultural heritage objects due to their optical setup, which allows to conduct and quantify...

Rock art paintings present high sensitivity to light, and an exhaustive evaluation of the potential color degradation effects is essential for further conservation and preservation actions on these rock art systems. Microfading spectrometry (MFS) is a technique that provides time series of stochastic observations that represent color fading over ti...

Figure S1a. Obverse and reverse view of 39 denars given in the same order as in Table 1. Figure S1b. Obverse and reverse view of 39 denars given in the same order as in Table 1. Figure S2. X‐ray fluorescence (XRF) maps obtained for denar 18246610 showing the net peak areas of (a) Ag Kα, (b) Ag Lα, (c) Cu Kα, (d) Pb Lα, (e) Au Lα and (f) Bi Lα. F...

This paper discusses a methodology that involves the use of X‐ray fluorescence (XRF), high‐energy particle‐induced X‐ray emission (HE‐PIXE) and high‐energy particle‐induced γ‐ray emission (HE‐PIGE) spectroscopies for the study of historic denars with the aim of describing the advantages and limitations of each technique as well as arriving at an ar...

A depth profile‐scanning study of an 18th‐century gun‐powder horn as well as reference Baltic amber samples was performed using a Raman confocal microscope equipped with a 785‐nm laser. It was found that spectra collected from the surface are different than those from the bulk. The main changes are observed in the 1,700–1,400 cm−1 range and are cau...

Surface enrichment of silver-copper alloys is a current subject of research in archaeometry, while its origin in cultural heritage objects remains unclear. Due to their low penetration depth, surface techniques may give misleading results if the objects analyzed show this enrichment behavior. To study this effect, the surface and bulk composition o...

In this study, two very promising techniques, micro X-ray fluorescence (μXRF) and laser-induced breakdown spectroscopy (LIBS) were applied to the examination of Polish banknotes – Polish zloty (zl). Several areas on each banknote were selected and analysed. Different elemental compositions were identified after comparing the spectra recorded from v...

Microfading Spectrometry (MFS) is a method for assessing light sensitivity color (spectral) variations of cultural heritage objects. Each measured point on the surface gives rise to a time-series of stochastic observations that represents color fading over time. Color degradation is expected to be non-decreasing as a function of time and stabilize...

The material composition of seven historical aquamanilia from museum collections in Kraków and Gdańsk were examined using X-ray fluorescence (XRF) spectrometry and micro-ablation sampling by means of laser-induced breakdown spectroscopy (LIBS) to better understand the materials found in these objects as well as for providing information that can be...

The documentation of archeological sites requires the adoption of non‐destructive techniques to safeguard the unique legacy coming from prehistoric periods. This article tackles the assessment of lightfastness properties on a rock art site to determine the behavior of motif's color deterioration over time in Remígia Cave, Castellón (Spain), which i...

Paper‐based heritage objects on exhibition are typically framed using a transparent glazing material such as glass or acrylic. This often makes the task of measuring their light fastness a difficult one since cultural institutions may have unframing restrictions, especially for large‐format objects. However, a testing programme recently conducted a...

The chemical identification of materials is the first step for developing and implementing recommendations for the care and display of resin cast and plastic objects in museum collections. This paper presents advantages as well as limitations of portable Raman. Therefore, a comparative analysis of portable and benchtop Raman instruments was perform...

In this unique collection the authors present a wide range of interdisciplinary methods to study, document, and conserve material cultural heritage. The methods used serve as exemplars of best practice with a wide variety of cultural heritage objects having been recorded, examined, and visualised. The objects range in date, scale, materials, and st...

In this unique collection the authors present a wide range of interdisciplinary methods to study, document, and conserve material cultural heritage. The methods used serve as exemplars of best practice with a wide variety of cultural heritage objects having been recorded, examined, and visualised. The objects range in date, scale, materials, and st...

In this unique collection the authors present a wide range of interdisciplinary methods to study, document, and conserve material cultural heritage. The methods used serve as exemplars of best practice with a wide variety of cultural heritage objects having been recorded, examined, and visualised. The objects range in date, scale, materials, and st...

The collection of denarii from the time of development of a Polish medieval state was studied using the proton induced X-ray emission spectroscopy. The major elements detected for these denarii are Ag and Cu, while minor elements such as Pb, Fe, Au, Bi, and Zn may also be present. The aim of the study was to cross-compare the results with a previou...

An investigation of a numismatic collection of silver denarii from the early Piast dynasty was conducted using Fourier-transform infrared spectroscopy. The studied coins, minted between 995 and 1020 ad under the rules of Boleslaus the Brave and Mieszko II Lambert, belong to the collection of the National Museum in Kraków. Fourier-transform infrared...

A series of 20 denarii from Boleslaus the Brave (992–1025) and Mieszko II Lambert (1025–1034), corresponding to the beginning of the Polish state were studied using the voltammetry of immobilized particles (VIMP) methodology. VIMP experiments, applied to nanosamples of the corrosion layers of the coins in contact with aqueous acetate buffer, provid...

The goal of this work was to analyze the profile of microbial volatile organic compounds (MVOCs) emitted by moulds growing on silk samples in search of particular volatiles mentioned in the literature as indicators of active mould growth. The selected moulds were inoculated on three types of media: (1) samples of pure silk placed on microbial media...

The goal of this work was to analyse the profile of Microbial Volatile Organic Compounds (MVOCs) emitted by moulds growing on silk samples in search of particular volatiles mentioned in the literature as indicators of active mould growth. The selected moulds were inoculated on three types of media: (1) samples of pure silk placed on microbial media...

The goal of this work was to analyse the profile of microbial volatile organic compounds (MVOCs) emitted by moulds growing on parchment samples, in search of particular volatiles mentioned in the literature as indicators of active mould growth. First, the growth of various moulds on samples of parchment was assessed. Those species that showed colla...

A study was undertaken to record and examine silver coins believed to be ancient Roman in origin. The aim was to evaluate the suitability of various advanced, non-invasive optical and spectrometric techniques for analysing the physical characteristics and elemental composition of numismatic objects. The questions addressed included the characteriza...

Full book chapter available at: https://www.researchgate.net/publication/322696760_Beyond_Photography_An_interdisciplinary_exploratory_case_study_in_the_recording_and_examination_of_Roman_silver_coins

The goal of this work was to determine the microbial volatile organic compounds emitted by moulds growing on wool in search of particular volatiles mentioned in the literature as indicators of active mould growth. The keratinolytically active fungi were inoculated on two types of media: (1) samples of wool placed on broths, and (2) on broths contai...

The identification of forged and genuine historical banknotes is an important problem for private collectors and researchers responsible for the care of numismatic collections. This paper presents a research approach for detecting material differences in historical banknotes through the use of microfading spectrometry along with other techniques su...

This exploratory, interdisciplinary case study of ancient Roman silver coins involved examination and digitization of two test coins. Various non-invasive imaging and analytical techniques were applied to identify and examine the properties and features of the coins, and to compare and evaluate the methods and multimodal results.

Non-European dyed materials other than textiles have received comparatively little systematic analysis, this is particularly true for objects made with dyed porcupine quills. This paper presents a comprehensive study of a group of Athapaskan porcupine quill specimens collected in 1862 which are held within the collections of National Museums Scotla...

Documentation of material cultural heritage is a core common interest to the participants of the network ‘Colour and Space in Cultural Heritage’ (www.COSCH.info), supported by the European Cooperation in Science and Technology (COST) between 2012 and 2016. Although COSCH is a trans-domain Action in Materials, Physics and Nanosciences (TD1201) many...

The main goal of this work was to optimize the SPME sampling method for measuring microbial volatile organic compounds (MVOCs) emitted by active molds that may deteriorate historical objects. A series of artificially aged model materials that resemble those found in historical objects was prepared and evaluated after exposure to four different type...

A case study to evaluate the use of microfading spectrometry (MFS) for the study of colored systems found in prehistoric rock art paintings was conducted in the Cova Remígia rock-shelter, Castellón (Spain). This rock shelter is part of the rock art sites of the Mediterranean basin on the Iberian Peninsula included in UNESCO’s World Heritage List. S...

X-ray fluorescence (XRF) analysis has become a standard method in archaeological science due to its non-invasive and non-destructive nature. This technique has extensively been used for the study of numismatic collections since the data derived from it can be correlated with manufacturing processes, provenance of raw materials, and geographical dis...

Consolidation treatments are commonly employed in museum conservation studios for treating biologically deteriorated wooden cultural heritage objects. Impregnation using either a solvent/resin or a polymerizing system is an example of such an intervention, which is often difficult to describe in terms of its behavior within the object’s structure....

Micro-fading spectrometry is a technique that combines visible reflectance spectroscopy and accelerated light aging testing. Therefore, it is a useful tool for determining the light-stability of dyes applied on textile substrates in a relatively short amount of time. Traditional accelerated light aging methods usually require controlling many varia...

In 1695, the Valencian artist Vicente Guillo was engaged in painting the vault of the Sant Joan del Mercat church in Valencia, Spain. After preliminary work was carried out, his contract was cancelled. In 1697, Antonio Palomino, renowned for the publication of his technical treatise entitled El Museo Pictorio y Escala Optica, was finally selected a...

Light fastness tests conducted on several areas of a light‐sensitive material may sometimes show inconsistent fading rates. These different fading behaviours suggest that colorants are not evenly distributed over the substrate surface or may be attributed to texture variations of the material. A mathematical model has been developed to help explain...

The use of inert gases for displaying sensitive objects and for the treatment of artifacts infected with bio-deteriorating agents is a current practice in many cultural institutions around the world. However, some artifacts may also experience color changes as a result of exposure to light in these reducing environments. Therefore, it becomes essen...

This paper presents the results of a light levels survey conducted at the Donald W. Reynolds Center for American Art and Portraiture in Washington DC. The museum space is shared by the National Portrait Gallery and the Smithsonian American Art Museum. After six years of extensive renovations, the building reopened to the public in July 1, 2006. The...

Accurate estimates of cumulative light exposure are an important prerequisite for the assessment and limitation of photochemical damage to museum objects on display The task is complicated because spotlights used to highlight particular features illuminate objects' surfaces unevenly and also because indirect light sources, for example diffuse sunli...

It is frequently assumed that sensitive museum materials follow the reciprocity principle of light exposures. Thus, equivalent exposure doses obtained by using either high-illuminance levels for short periods of time or lower illumination for longer exhibition periods are believed to cause similar degrees of damage to an object. Microfading spectro...

A series of light-fastness tests were conducted on a group of ethnographic objects that will be on exhibit at the Smithsonian Institution Arctic Studies Center, a recent addition to the Anchorage Museum at Rasmuson Center in Alaska. The objects surveyed belong to the collections of the Smithsonian National Museum of Natural History and the Smithson...