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1.
The Sos Furrighesos necropolis (Anela) is considered to be one of the most important funerary monuments in Sardinia. The hypogeum consists of various graves, called Domus de Janas, which are decorated with Neolithic mural paintings and sculptures. This work was undertaken in order to clarify which techniques were used in the past, through the identification of pigments and binding media. The samples, scraped off from the paint surface, were studied by using various analytical techniques in order to characterise both the pigments and the binding media. The main problems concerning the characterisation were due to the small sizes (1–5 mg) of the samples and their complex nature. As regards pigments, X-ray diffraction and scanning electron microscopy-energy dispersive X-ray spectrometry analyses were performed on the samples. These techniques are well suited to the characterisation of inorganic pigments and have led to the identification of the red pigment as haematite. In order to characterise the organic binders, the samples were analysed by a procedure based on a gas chromatography–mass spectrometry technique, which allows proteinaceous and lipidic media determination in the same sample. In most of the samples, the presence of egg was suggested.  相似文献   

2.
Forty-six Streptomyces strains were isolated from paintings and stone surfaces from Tell Basta and Tanis tombs (80 km south-east Cairo, Egypt). Eight of these strains were selected to determine their sensitivity against 13 antibiotics. In general, high levels of resistance could be observed. Gentamycin, spiramycin and doxycycline were the most effective antibiotics against the majority of strains under study. Due to the observed antibiotic resistances, gamma irradiation was studied as a possible alternative to inhibit microbial growth. Isolated bacteria were exposed to different doses of gamma irradiation (5, 10, 15, 20 and 25 kGy). The growth of all Streptomyces isolates except S. canarius was completely inhibited at 25 kGy. The applied doses of gamma irradiation did not cause any observable alterations or colour changes to pigments and binding media (arabic gum, animal glue and egg-yolk) used in the paintings.  相似文献   

3.
Red lake pigments and dyes used in works of art were characterized by microspectrofluorimetry, a new tool in the field of cultural heritage. Emission and excitation spectra were obtained with high spatial resolution (8–30 μm) in cross-sections from paintings by Vincent van Gogh and Lucien Pissarro and from millenary Andean textiles. The fluorophores were identified by comparing their spectra with those from historic reconstructions assembled in a database. In the paints, purpurin and eosin lakes were detected. In the Paracas and Nasca textiles, dated from 200 B.C. to A.D.1476, purpurin and pseudopurpurin were the red dyes used. Carminic acid was detected in textiles dated close to the Inca Empire, A.D. 1000–1476. The results obtained with this new technique were confirmed and are in agreement with those obtained with conventional methods, requiring microsampling, such as HPLC-DAD-MS and SEM-EDX.  相似文献   

4.
Giovanni Fattori (Livorno 1825–Firenze 1908) is the most representative artist of the Macchiaioli's current, an early group of Italian plein-air artists, whose work anticipates, in the xixth century, that of their younger contemporaries, the French Impressionists. The study, performed by a multidisciplinary team made up of scientists and conservators, presents the results of the scientific characterization carried out on a group of 10 paintings made by Fattori between 1854 and 1893 and shows the way he used complex mixtures of a large variety of traditional and synthetic pigments, ranging from lead white, found pure and also extended with calcium carbonate, natural barite and gypsum to zinc white, from red ochre to cinnabar and vermilion, from yellow ochre and Naples yellow to chrome yellow, cadmium yellow and zinc yellow, combined with many other ones reported in details. This paper highlights the evolution of his painting technique during a time of great technological and social innovations and puts forward some hypothesis on his awareness about manufactured pigments, i.e. tube paints recently introduced into the artists’ circles. The wide range of pigments and their different quality among the same synthetic products suggest that the artist used all the available materials, and that picking out the pigments he retained the early xixth century artists techniques, such as the use of mineral earths and Prussian blue, similarly to his contemporary Italian artists Federico Zandomeneghi and Telemaco Signorini, but he also experimented new and peculiar pigment mixtures in the making of “colored darks” and an innovative use of the grounds in the final composition, that are also distinctive features of the French Impressionists. This work is aimed at contributing to overcome the lack of a comprehensive overview on the widespread historical and scientific data collected up to now on the Italian paintings in the xixth century, which has been severely underestimated with respect to previous art movements.  相似文献   

5.
The paper presents our results concerning a complex investigation by reflectance spectroscopy (RS) and Electron Paramagnetic Resonance (EPR) of the defects induced by gamma irradiation in 22 different historical pigments. Gamma irradiation is used to destroy microflora and insects which are involved in biodeterioration processes of art works such as paintings. At the same time, it can induce defects i.e. color centers which are likely to modify the original painting colors by altering the embedded pigments. Accordingly, RS was used to quantify, by means of CIELAB color space, the contribution of irradiation defects to the pigments color changes, while EPR spectroscopy, in view of paramagnetic properties of color centers, was used to confirm their presence after irradiation. Our investigations showed that, excepting marble dust whose color alteration was still observable after 3 months, color changes induced by irradiation in all other pigments disappeared after about 30–40 days. In addition, RS as well as EPR measurements suggest that color changes are related to irradiation color centers, this finding being confirmed by the coincidence, within experimental uncertainties, of the half-life time color changes as obtained by these methods.  相似文献   

6.
In the present article an attempt is made to elucidate the organic colorants commonly encountered in the Russian avant-garde painting palette by a combined art historical, documentary and physicochemical investigation, and to examine the influence of environmental factors on the chromatic profile originally sought by the artist. The overall approach based on written sources is confirmed by measurements on relevant paintings. The documentary research deals with the influences of Orthodox iconography, folkloric art, and occidental modernist tendencies on the Russian avant-garde palette, and studies the effects of contradictory historical processes in the chromatic profile of individual paintings. In the experimental section a series of colorants are investigated concerning the effects of accelerated ageing on experimental painting tables, prepared as watercolor and gouache layers on paper ground. The resulting samples are subjected to colorimetric and spectroscopic measurements, and analogous analytical procedures are applied on samples taken from selected paintings. A systematic comparative study of all data permits evaluation of the materials used in terms of their stability towards extrinsic factors, and proposal of degradation routes in order to assist museum curators and conservators in every concrete case related to the broad spectrum of pigments examined.  相似文献   

7.
Interactions of lead-based pigments with a number of inorganic salts, one of the most dangerous degradation agents of wall paintings, were studied under laboratory conditions. The results were used to interpret colour changes observed in 11th century frescoes from the church of Saint George in Kostoľany pod Tríbečom, the oldest preserved wall paintings in Slovakia. Interactions of selected pigments (lead white, massicot, red lead) with different salt solutions were performed within long-term laboratory experiments. We used a selection of naturally occurring salts (Na2SO4, MgSO4, CaSO4, NaCl, NaNO3, Ca(NO3)2, Na2CO3, K2CO3 and urea) and, additionally, a range of synthetic salts that are often applied to the wall paintings during their cleaning and conservation (NaHCO3, KHCO3, (NH4)2CO3, NH4HCO3). The reaction products were identified by X-ray powder diffraction. Red lead (Pb3O4) has a tendency to darken in all salt solutions containing dissolved atmospheric CO2 due to disproportionation to plattnerite (PbO2) and cerussite (PbCO3). Massicot (PbO) in a wet state reacts with atmospheric CO2 to form hydrocerussite and finally cerussite. Lead white (PbCO3 and Pb2CO3(OH)2) reacts with sulphates, carbonates and chlorides to form their respective salts in high yield and, sometimes, without any apparent colour change. Samples taken from the dark brown parts of the wall paintings in Saint George's church were analysed using laboratory X-ray powder microdiffraction. The presence of hydrocerussite, cerussite, plattnerite and lead magnesium carbonate was revealed. According to the results of laboratory experiments, the original lead-based pigment of the now darkened parts was red lead.  相似文献   

8.
The effects of a Q-switched Nd:YAG laser irradiation on a group of supports, painted with six different inorganic pigments, was investigated. The pigments were chosen from among the most utilized on painted historical surfaces: red ochre, yellow ochre, chromium green, ultramarine azure, white chalk and carbon black, and they were distempered with two binders – linseed oil and gypsum – on primed wood panels. The pigments were characterized by means of X-ray diffraction and Fourier transform infrared spectroscopy. Chromatic characteristics, chemical composition and surface morphology of the painted layers were investigated before and after the laser irradiation. Three different fluences were used to detect the correlation between laser parameters and changes in painting layer characteristics.  相似文献   

9.
The application of total reflection X-ray fluorescence (TXRF) to the analysis of inorganic pigments used in five Albanian icons painted by Onufri Qiprioti, in the period from the end of 16th to the beginning of 17th century is presented. After removing the protective varnish with a solvent, a dry cotton-wool bud (Q-tip) was rubbed over the painted surface to collect the micro-samples. Samples, covering the main colors and their hues, were collected of each icon. A part of the small amount of the sample was transferred to a glass carrier and analyzed by TXRF. Main types of inorganic pigments used for different colors could be identified. The results indicate a palette which included white lead, calcium white, gold, orpiment, yellow and red ochre, vermilion, red lead; a cooper based green pigment (malachite or verdigris) and smalt.  相似文献   

10.
This articles reports new discoveries relating to ground glass and silica in European easel paintings from the 15th to the 17th centuries that were created by various German, Italian and Netherlandish artists. The earliest known additions of these extenders date to the early 1430s. Glass powder of varying fineness, prepared from vessel or window cullet, is often found in red lake glazes as well as in other colours or preparatory layers of paintings. SEM/EDX analyses of the glass particles reveal a variety of chemical compositions (soda ash, wood ash, wood ash-lime, wood ash-lead, mixed alkali), which are discussed with respect to the provenance of the paintings. Historical sources on painting techniques mention glass additions most frequently to accelerate drying of oil paints, but also occasionally to facilitate grinding of pigments. Another possible function of powdered glass and silica, especially in oil-bound red lake glazes, is that of a transparent filler, as will be here discussed based on paint trials.  相似文献   

11.
This paper deals with the impact of soluble salts on the deterioration of wall paintings in the region of Wadi El Natrun in Egypt, including the identification of the building materials and pigments used. For this purpose we used XRD analysis which proved that the green pigment in the Church of the Virgin, Wadi El Natrun is a mix of malachite and hydrocerussite, and the black pigment is graphite. The results proved that the building materials (stones, mortar, and plaster) in Wadi El Natrun are affected by ground water as they have the same soluble salts at different concentrations. The Wadi El Natrun lakes are the native source of natron salt, which has been used in mummification techniques. Soda lakes represent the major types of naturally occurring highly alkaline environments. The factors leading to the formation of the alkaline saline deposits may be divided into climatic, geological, and topographical. Climatic and topographical factors control the amount of water entering the system as rainfall or surface runoff and the amount leaving by evaporation. Geochemical factors determine which ions enter the system. Solutions of carbon dioxide result in the formation of a weak carbonic acid, which dissolutes the mineral components of the surrounding rocks and archaeological buildings, leading to their ion release.  相似文献   

12.
The Carrera del Darro is a street within the city of Granada, Spain, which is emblematic owing to the architectural value of its buildings, to its significance for the urban structure of the city and to the implications it has for the surroundings of the Alhambra. Our study concerns the chemical analysis of the mural paintings on four façades, corresponding to numbers 23, 25, 27 and 29 of the Carrera del Darro. From the analysis of the mortar, it may be concluded that the composition is very similar, though not identical, in the four paintings studied: a limestone mortar. Ochre, white, black and red were used for the decoration of the four façades; green pigment was also observed in the second decoration of no. 29. The results of the morphological examination and EDX microanalysis of the paint samples are shown. By means of the thermogravimetric analysis we established the existence of an organically derived compound. After the existence of an oleaginous binder had been discounted by gas chromatography/mass spectrometry (GC/MS) analysis, we continued with the extraction and determination of proteins by spectrophotometry analysis, detecting low levels of proteins in the paint on the four façades analysed. The study was completed by evaluating the influence on the deterioration of the paintings by the possible surface presence of salts (such as nitrates or chlorides) and organic compounds.  相似文献   

13.
The source of the previously unassigned weak band at 2340 cm−1 that is occasionally observed in the infrared spectrum of natural lapis lazuli pigment is here attributed conclusively to CO2 trapped in the β-cage of lazurite. In addition, the geo-sourcing potential of this infrared feature for lapis lazuli is tested and found to be more ambiguous than previously suggested. The CO2 absorption band is in fact observed in lapis lazuli samples from numerous disparate geographic locales including Afghanistan, Canada, Myanmar, Siberia, Tajikistan, and the Ural Mountains, as well as mineral hauyne samples from Germany and Italy. The spectral feature was absent from lapis lazuli samples from California, Chile, Colorado, and New York. Furthermore, poor quality lapis lazuli samples, regardless of locale, highly processed natural pigment samples, and all samples of synthetic ultramarine blue, green, and violet pigments were devoid of encapsulated CO2.  相似文献   

14.
Zinc oxide nanoparticles were prepared and used for surface treatment of oil paintings painted on paper supports. The prepared coating mixture containing 2% of ZnO nanoparticles showed excellent transparency. The effect of coating on protecting the paper support and paintings against microbial attack by Trichoderma reesei and Aspergillus niger, dirt accumulation, and UV aging was studied. Coatings containing ZnO nanoparticles enhanced the durability of linseed oil-based paintings toward UV aging regarding the change in color. Coatings containing ZnO nanoparticles improved resistance to microbial attack when subjected to inoculums containing T. reesei or A. niger fungi. In addition, coatings containing ZnO nanoparticles reduced accumulation of dirt on oil paintings when left in open air for 6 months; cleaning of paintings was quite easy compared to the non-coated paintings or those coated with the varnish without ZnO nanoparticles.  相似文献   

15.
Optical and SEM-EDS microscopy, X-ray powder diffraction and micro FT-IR spectroscopy investigations of the funerary klinai (couches) of Tomb 1 from Amphipolis and a stone sarcophagus from ancient Tragilos—two painted monuments made by Macedonian craftsmen of the Early Hellenistic period—identified the original materials and painting technique, as well as synthetic materials used as consolidants during past restoration treatments. The original organic binders and the superficial modern coatings have been identified by micro FT-IR spectroscopy applied directly to the sampled powders or tiny fragments and to their solvent—soluble fractions. The pigments identified on the couch of Amphipolis are: red and yellow ochre, cinnabar, Madder lake, paratacamite and antlerite, carbon black, calcium carbonate, kaolin and gypsum. The identification of egg and animal glue confirms the application of tempera and secco techniques. The detection of polymers such as polydimethylsiloxane, polyvinyl acetate and alkyd resins, is related to modern restoration products. The pigments attested on the paintings of the Tragilos' sarcophagus are: red and yellow ochre, Egyptian blue, malachite, carbon black, calcium carbonate and gypsum. The absence of organic binders combined with the constant presence of calcium carbonate in all the examined samples suggests the use of lime as the binding medium in the painted decoration of the sarcophagus. The presence of Paraloid B72 is related to recent conservation treatments.  相似文献   

16.
Organic binding media found in paintings exhibit characteristic fluorescence properties that strictly correlate with their chemical composition and may vary as a function of the ageing time. The aim of this work was to investigate the capability of microspectrofluorometry to distinguish between different binders. Linseed oil and protein-based media, deposited as thin films on microscope glass slides both in the presence and in the absence of inorganic pigments, were examined before and after artificial photo-ageing. Cross-sections of some paint layers were also examined. The article points out that microspectrofluorometry coupled with deconvolution analysis can be a useful tool for distinguishing between oil- and protein-based media. The curve-fitting analysis furnished a fine characterization of each binder/pigment combination, and highlighted the small spectral differences between their fluorescence signals.  相似文献   

17.
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18.
The sculptural polychromy in the Zhongshan Grottoes, sited in northwest China, has been investigated in terms of chemical composition of employed materials and pigments, state of conservation and painting technique. Raman analysis, Fourier-transform infrared analysis, analysis through energy-dispersive X-ray spectrometry coupled to scanning electron microscopy and pyrolysis coupled to gas chromatography and mass spectrometry were applied. Six analyzed samples showed silicates and kaolin as main components of the ground layers. Also lead white has been found in these layers. Minium, red-earth and mercury sulfide are the red pigments detected in the polychromy. A mixed use of malachite and atacamite has been detected in three green samples. Optical characteristics of atacamite and malachite found in the samples indicate a synthetic origin. The presence of a synthetic organic pigment such as phthalocyanine chlorinated pigment was also revealed. Ultramarine blue pigment, obtained by purification of lapis lazuli, has been detected in the blue sample. As for the binders used, fatty materials and siccative oil were found.  相似文献   

19.
This paper presents the first extensive investigation of the composition of both the organic and inorganic media used by Lorenzo Lotto, one of the outstanding artists of the Italian Renaissance in the early 16th century. By investigating four paintings from The State Hermitage Museum collection (Saint-Petersburg, Russia), new insights into the artist's painting techniques were obtained, which contribute to our understanding of the transition from egg tempera to oil painting techniques that took place in Italian paintings between the 15th to the mid 16th century. Inorganic materials were determined using SEM-EDX and PLM, revealing information on the artist's palette. Of particular note was the powdered colourless glass found in the priming layer of the Madonna delle Grazie, which was most likely used as dryer. Organic materials were analysed in individual paint layers using GC-MS, and revealed a mature use of drying oils as paint binders, skilfully mixed with other organic materials and inorganic driers, to obtain the desired aesthetical and technical qualities of the paint. The study revealed that Lotto used the tempera grassa technique through most of his creative life.  相似文献   

20.
Pollutants and their potential degradation of paintings have been measured for the first time in microclimate frames (mc-frames), which are used to protect paintings. The pollutants that were measured include both inorganic pollutants, which originate mainly from external sources, and organic pollutants from mainly internal sources. Those originating from the outdoors enter rooms and subsequently mc-frames at a rate depending on the ventilation rates (air exchange rates) of the mc-frames. The concentration of gaseous pollutants emitted within the mc-frames will depend on net emission rates of the materials used to make the mc-frames, their design, and their ventilation rates. In the EU PROPAINT project measurements of gaseous air pollutants and climatic conditions were performed at various locations both inside and outside different state-of-the-art mc-frames. Diffusive passive pollution gas samplers were used together with different types of dosimeters. Results show that the dosimeters respond to either the photo-oxidizing conditions or the level of volatile organic acids in the environments both in the museums and within the mc-frames. Two dosimeters, the Early Warning Organic (EWO) made from a synthetic polymer and the Resin Mastic coated Piezo electric Quartz Crystals (RM-PQC) respond to photo-oxidation and showed higher values outside than inside the mc-frames. Two other dosimeters, the Glass Slide Dosimeter (GSD) and the Lead coated Piezo electric Quartz Crystals (L-PQC) respond to volatile organic acids and yielded higher values inside than outside the mc-frames. This study emphasizes the need for further work to determine environmental damage functions for paintings, in particular for the effects of organic acids. Such information is essential for the evaluation of the protective effects of mc-frames for paintings. The use of mc-frames is increasing and it is very important to know that this protective measure does not introduce new risks.  相似文献   

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