Handheld X-ray Fluorescence Research Articles

Heterogeneous characteristics and controlling factors of oil bearing of the Chang 7 shale in the Ordos Basin

Oil-bearing evaluation is the key issue of shale oil geologic exploration, which affects the mobility and effective development of the remaining oil in the shale system. To study the oil content and its controlling factors of shale in Chang 7 member of the Yanchang Formation in the Ordos Basin, we take the core of well H317 as the main research object, analyze the oil-bearing characteristics of shale by conventional rock pyrolysis and multistep pyrolysis experimental methods, and analyze the change characteristics of the elements by handheld X-ray fluorescence. The results indicate that the organic heterogeneity of Chang 7 shale in well H317 is obvious. It can be divided into upper shale and lower shale with 2467 m as the boundary. The upper shale has low total organic carbon (TOC), poor kerogen type, and slightly low oil content, but strong mobility. The lower shale has high TOC, good kerogen type, and good oil content, but poor mobility. The content and type of organic carbon in shale have obvious control effect on oil bearing and mobility. Differences in paleosedimentary environment control the formation of original sedimentary organic matter. During the lower shale deposition period, the climate was humid and the terrigenous input was relatively weak, high paleoproductivity and strong reducing water effectively preserved the original sedimentary organic matter, and finally formed an organic-rich interval with high TOC. Early diagenesis further altered the abundance and type of original organic matter.

Understanding the chemical and mineralogical composition of commercial henna and jagua tattoos and dyes—a multi-analytical approach

Temporary tattoos and dyes constitute a great analytical challenge in relation to the regulatory control of their ingredients. Most of these commercial products are not labeled according to their content and their chemical nature is highly diverse. Therefore, it is necessary to analyze these complex samples to evaluate the potential presence of metallic impurities, to ensure the safety of cosmetic products contributing to health protection. This study proposes a multi-analytical methodology, which includes handheld X-ray fluorescence (h-XRF) and X‐ray diffraction (XRD), complemented by variable pressure scanning electron microscopy coupled with energy-dispersive X‐ray spectrometry (VP-SEM–EDS) to fully characterize 34 commercial samples of jagua and henna tattoos and dyes. The approach allowed the identification of the main constituents providing complementary compositional data and differences between sample types were established. In addition, information on the degree of natural pigments homogeneity was also obtained. The results’ discussion considering the current European cosmetics regulation may be useful to support the drafting of safety requirements and specific regulation.

Sequence Stratigraphy, Depositional Environment and Associated Lithofacies of Lacustrine Shale: A Case From the Upper Fourth Member of Shahejie Formation, Dongying Depression, Bohai Bay Basin

The lithofacies assemblages in the lacustrine shale of the Shahejie Formation in the Dongying Depression have different compositions due to the complex depositional climate, lake water conditions, and sediment supply. Hence, the lithofacies types and depositional conditions were analyzed based on parasequence division and lithofacies classification. According to gamma ray integrated prediction error filter analysis (INPEFA), handheld x-ray fluorescence (XRF) measurements, mineral composition, total organic carbon (TOC) content, and sedimentary structures, six parasequences (P1–P6 from bottom to top) were identified, and seven lithofacies are recognized: (1) organic-poor thin-bedded calcareous mudstone, (2) organic-poor laminated calcareous mudstone, (3) intermediate-organic laminated calcareous mudstone, (4) organic-rich laminated calcareous mudstone, (5) organic-rich calcareous shale, (6) organic-rich laminated carbonate-bearing mudstone, and (7) laminated silty mudstone. When the climate became warm and wet, the water level of the lake increased with a decrease in salinity, and the corresponding lithofacies assemblages in the P1 to P2 parasequences gradually changed from organic-poor thin-bedded and laminated calcareous mudstone to intermediate-organic and organic-rich calcareous shale. When the climate became humid and warmer, resulting in an increasing water level and terrigenous input, the lithofacies assemblages in the P3–P4 parasequences changed from organic-rich calcareous shale and laminated carbonate-bearing mudstone to laminated silty mudstone and calcareous mudstone. At the end, the climate became slightly drier and cooler with a decrease in the water level, and the P5 and P6 parasequences were dominated by intermediate-organic and organic-poor laminated calcareous mudstones. Through elemental analysis and lithofacies observation, we found that the redox conditions of the water may have changed over time. Among the parasequences, the water column of the P2 parasequence was mainly stratified by salinity, that of the P4 parasequence was mainly stratified by temperature, and that of the P3 parasequence was in transition. The synergistic effect of various factors played a key role in the enrichment of organic matter. This study highlights the depositional processes of the lithofacies assemblages in a lacustrine shale and contributes to the understanding of shale oil accumulation in lacustrine shale.

Study supporting restoration of rapakivi granite in St. Petersburg

The focus of this ongoing study has been on two rapakivi granites, wiborgite and pyterlite, that have been utilized in St Petersburg since the 1760s but originate from south-eastern Finland. The aims of this study have been to describe the two types of rapakivi granites in their geological settings, to assess the needs for restoration of stones utilized in constructions and to establish databases of stones utilized in historical buildings and of the original and alternative quarries. The focus of this study has been on defining the original quarries for the old building stones or finding other similar substitute granite deposits. Chemical analysis with a handheld XRF instrument was found to be the most promising approach when combined with multivariate mathematical tools. In addition, the applicability of chemical treatment of the surface of rapakivi granite for changing the appearance of stones was investigated. The visual appearance and texture of natural stones used in restoration are the key factors, in addition to the stone type and quality. The chemical treatment of stone surfaces using acidic or metal salt treatments altered the colour tone and visual pattern. Thermal treatment was also found to be effective, but it might be harmful to the surface structure. With further optimisation, chemical treatment could be a feasible method to change the visual appearance of fresh stone in the case of substitution of weathered stone. In addition, this project has initiated cross-border activities that aim to create opportunities for establishing first contacts between the authorities, construction companies, stone producers and the manufacturer who produces the needed high-quality stone pieces.

Challenges in Using Handheld XRFs for In Situ Estimation of Lead Contamination in Buildings

Lead in buildings can be found in certain materials such as paints or can be a result of contamination during the use stage. In situ methods for lead identification can be vital for the proper treatment of hazardous CDW (from repair works or selective demolition). A conventional handheld XRF (HHXRF) spectrometer can be used for this purpose, and this study analysed its reliability. A laboratory experiment was conducted to test different calibrations, and to establish a procedure for the conversion of the HHXRF lead concentrations into lead loadings. Model latex paint with a constant lead content was used on two types of surfaces (plasterboard and concrete). A field study was performed to identify and quantify the lead in paint on masonry walls in a public building. ICP-MS analysis was performed in order to verify the lead content. The coefficients of proportionality in the proposed model depend on various parameters: the contamination type, the layer thickness, the substrate, and the built-in calibrations. Despite the limitations of the HHXRF and the discrepancy of the mean lead loadings from the HHXRF and ICP-MS analysis, the HHXRF can be useful for the identification of lead in paint layers up to 1 mm, with a low limit of detection of the order of 0.01 mg/cm2 at worst.

Patterns and forms of copper and cobalt in Macrotermes falciger mounds of the Lubumbashi area, DR Congo

Using termite mounds as sampling medium for geochemical exploration is based on the assumption that mound construction results in upward transfer of particles that could reflect the composition of the underlying material. For large mounds such as those constructed by Macrotermes species, this is complicated by their dimensions and age. To investigate whether and how such mounds can be sampled to provide information about the nature of subsurface deposits, two Macrotermes falciger mounds built over mineralized deposits were sampled. For comparison, the soils around those mounds, as well as four control mounds in areas without mineralized deposits, were also sampled. Copper and cobalt concentrations were measured using hand-held XRF spectrometry, and chemical speciation analyses were performed for selected samples. The termite mounds built on mineralized deposits contained up to 9 times more Cu than the surrounding soils and up to 13 times more than termite mounds built over non-mineralized deposits. Cobalt concentrations were well above the detection limit in mounds on mineralized deposits, with values of up to 630 ppm, in contrast to the surrounding soils and the control mounds. Copper concentrations were found to be highest in the central basal part of the metal-bearing active mound. The speciation study showed that Co was predominantly in reducible form, whereas Cu was predominantly in both reducible and residual forms. Sampling of large termite mounds is confirmed as a possible tool in Cu-Co prospection, whereby it must be taken into account that metal distribution within the mounds is neither uniform nor static.

Characterization of inorganic elements in common consumer plastics using handheld X-ray fluorescence analyzer.

Plastics are increasingly being used in consumer products due to its versatility in many applications. However, these plastics may contain inorganic elements that may be harmful to humans. To determine any potential health risk of plastics, it was important to characterize elemental composition of plastics and assess usage patterns. To investigate plastic usage in a typical Jamaican household and to characterize the inorganic elements in consumer plastics using XRF analyzer. About 200 questionnaires were distributed to households to determine the types and quantity of plastics. A total of 130 plastic samples from 7 categories were collected and measured for inorganic elements using handheld XRF. Household plastics were mainly used for storage and personal hygiene products. On average, 10% of plastics were recycled, while 30% were burned. Inorganic elements present in plastic samples were Cl > Ti > Ba > Fe > Zn > Sb > Cr > Br > Cu > V > Pb > As. Elemental concentrations varied based on the category of plastics. Green plastics had the highest concentrations of each type of elements. This study provided useful information on characterizing the different types of elements present in common household plastics. Results from the survey were used to assess participants' attitude and behaviors towards plastics usage and disposal. It was important to obtain a profile of plastics waste from a typical household. This will allow for more targeted strategies to reduce plastics pollution.

Tutankhamun’s Polychrome Wooden Shawabtis: Preliminary Investigation for Pigments and Gilding Characterization and Indirect Dating of Previous Restorations by the Combined Use of Imaging and Spectroscopic Techniques

Abstract To the best of our knowledge, such a detailed study on polychrome wooden shawabtis of King Tutankhamun (18th Dynasty in ancient Egypt) has not been reported in the literature, so the purpose of our study is to noninvasively identify the polychrome layers and previously applied materials for a number of wooden shawabtis that belong to King Tutankhamun through a protocol based on imaging techniques integrated with single-spot spectroscopic techniques. In the first step, imaging techniques (visible, ultraviolet induced visible luminescence, ultraviolet reflected, visible-induced infrared luminescence, infrared reflected, and infrared false color) and optical microscopy were applied to gather information and provide evidence on the distribution of original and previously applied materials on the polychrome surfaces. In the second step of our work, we analyzed the selected areas with single-spot analyses (handheld X-ray fluorescence spectroscopy and visible reflectance spectroscopy) and X-ray diffraction analysis. The materials of the previous restoration interventions were studied by Fourier transform infrared spectroscopy. The application of a protocol based on imaging techniques integrated with data obtained from single-spot spectroscopic techniques allowed the characterization of a remarkable number of polychrome layers and some previous restoration materials and mapping of their distribution on the original surface, which provides not only essential data for the follow-up treatment and conservation works but also offers important information for the study of polychrome wooden shawabtis of other periods in ancient Egypt.

Study of controlled migration of cadmium and lead into foods from plastic utensils for children.

Lead (Pb) is a highly neurotoxic chemical element known for reducing intelligence quotient (IQ) and promoting antisocial behavior in children and adolescents, while cadmium (Cd) is a carcinogenic bioaccumulative element. Both these metals are included in the priority pollutant list of the United States Environmental Protection Agency and in the WHO List of Chemicals of Major Public Health Concern, where contaminated foods and beverages are the most common pathways of exposure. The objective of this study was to determine total Cd and Pb levels in colored plastic utensils (cups, mugs, bowls, feeding bottles, and plates) for use by children and to measure the specific migration of these elements into beverages and foods. Total contaminant levels were determined using a handheld X-ray fluorescence analyzer. Specific migration tests were conducted using the simulant solutions acetic acid 3% (m/v) and water. Migration levels were determined by ICP-MS. Specific migration tests for Pb were also performed on commercially available samples (cola soft drink, orange juice, vinegar, and milk), with levels determined by graphite-furnace atomic absorption spectrometry (GF-AAS). A total of 674 utensils were analyzed in loco at major commercial centers in Greater São Paulo, of which 87 were purchased for containing Cd and Pb concentrations above permitted limits. Mean concentrations of the metals detected in the purchased utensils were 1110ppm for Pb and 338ppm for Cd. For specific migration assays, Pb levels were 187, 13, and 380 times above the permitted limit (0.01mg.kg -1) for acetic acid, water, and orange juice, respectively. Cd levels were 50 and 2.4 times above the maximum permitted limit (0.005mg.kg -1) for acetic acid and water, respectively. The districts where the utensils were purchased were grouped according to their social vulnerability index and compared using ANOVA. Pb levels were different between low and medium/high social vulnerability groups (p = 0.006). The findings corroborate the initial hypothesis that these utensils constitute a major source of exposure to PTEs such as Cd and Pb, pointing to the need for stricter regulation and inspection by the Brazilian regulatory agencies.

Handheld XRF analysis of gold armlets with crescent-shaped terminals from the prehistoric collection of the Hungarian National Museum

In this study, we present the elemental composition results determined with handheld XRF method on the gold armlets with crescent-shaped terminals from the Prehistoric Collection of the Hungarian National Museum. In addition to the new Tápióbicske find, the Dunavecse, Biia, the Géza Kárász Collection find from Transylvania and the Körös area specimens were also included in the analysis. Based on the handheld XRF results, it can be concluded that most of the studied armlets have high Ag (21–24 wt%) and low Cu (0.06–0.17 wt%) content. These objects form a relatively uniform group (Hartmann A3) based on their elemental composition, regardless of their type and presumed date. Lower Ag content was only detected in the Körös area find (ca. 5.8 wt%) (Hartmann B) and in the rivets of the Biia armlet (ca. 12.3 wt%) (Hartmann L/Q2). Our results suggest that the studied armlets had a lower Ag content compared to the previous measurements on the Bilje, Pipea and Boarta armlets, made by different techniques (OES, SR XRF). The applied method is not suitable to determine the origin of the raw materials. Only the material type could be defined as native gold.

Comparison of X-ray Fluorescence (XRF) and Atomic Absorption Spectrometry (AAS) Results for an Environmental Assessment at a Mercury Site in Kyrgyzstan

Khaidarkan, Batken Province, Kyrgyzstan is home to one of the world’s largest and last primary mercury mines. Doctors without Borders (MSF) and the Ministry of Health (MOH) of Kyrgyzstan have found that the Batken region has an elevated rate of non-communicable diseases (NCD) within the country. NCD can be caused by environmental pollution. A human health risk assessment was conducted to investigate heavy metal exposure. Using a hand-held X-ray fluorescence (XRF) spectrometer for soil screening is faster and less expensive than reliance on bench-scale methods. To establish a site-specific mercury conversion factor between XRF and the local MOH lab’s Atomic Absorption Spectrometry (AAS) with a Pyrolyzer attachment, soil samples were collected in Khaidarkan and surrounding villages. Samples were analyzed by XRF in three stages: in situ, ex situ-bulk, and ex situ-sieved. The ex situ-sieved samples were analyzed by AAS. Analysis results indicate that in situ readings can be used as a qualitative tool for screening, and a conversion factor of 1.7 was most appropriate for converting ex situ-bulk/ex situ-sieved and AAS results. This analysis enables the MOH laboratory and others to use XRF as a quick and cost-effective monitoring tool for Hg contamination in soil.

Comparison of machine learning techniques for predicting porosity of chalk

Precise and fast estimation of porosity is a vital element of reservoir characterization. A new technology for fast and reliable porosity prediction of chalk samples is presented by applying machine learning methods and X-ray fluorescence (XRF) elemental analysis. Input parameters of prediction models are based on rapid and accurate elemental analysis of chalk samples obtained from Hand-held X-ray fluorescence (HH-XRF) measurements. The intelligent models, including Random Forest (RF), Multilayer perceptron (MLP), Random Forest integrated by Genetic Algorithm (GA-RF) and Multilayer Perceptron integrated by Genetic Algorithm (GA-MLP), are trained and tested based on samples consisting of outcrop chalk samples from Rørdal and Stevns Klint (ST) and core samples from Ekofisk Formation in the North Sea. Results are evaluated by sustainability index (SI), determination coefficient (R2), correlation coefficient (CC), and Willmott's Index of agreement (WI). Results indicate that the combination of GA-RF intelligent method with XRF elemental analysis successfully provides an accurate model by 0.99, 0.02, 0.995 and 0.99 respectively for CC, SI, WI and R2, respectively.

Investigating the utility of a handheld X-ray fluorescence (XRF) device as a field test for suspected ivory

Forensic or field investigators can use X-ray fluorescence (XRF) to determine the elemental profile of an item. The elemental composition of an item can subsequently be used to identify the source of that item when compared with the elemental compositions of known potential source materials. For example, illegal trafficking of animal parts, including ivory, requires investigators to identify that an item originated from an animal source. Here, we describe a quick and effective field test that enables law enforcement officers to differentiate genuine ivory, bone, and antler from fake ivory, and to seize genuine ivory items with greater certainty. We used a handheld XRF device to scan 445 items from 9 categories to represent a range of biological and non-biological materials that may be encountered in the field. We established an XRF Ivory Flowchart with ranges for ivory based on a calcium to phosphorus (Ca/P) ratio of 1.2–4.0 and a light element (LE) percentage range of 27%− 76%. Four volunteers used the XRF device to scan 21 items (9 ivory and 12 non-ivory items) in combination with the XRF Ivory Flowchart to effectively identify 97% of the ivory items and to eliminate 83% of the non-ivory items. We believe the utility of the XRF device combined with the XRF Ivory Flowchart provides law enforcement officers with a valuable tool to combat illegal ivory trafficking and can assist with efforts to eliminate the poaching of protected ivory-bearing species.

Portable X-ray fluorescence (pXRF) calibration for analysis of nutrient concentrations and trace element contaminants in fertilisers

With the increasing popularity of local blending of fertilisers, the fertiliser industry faces issues regarding quality control and fertiliser adulteration. Another problem is the contamination of fertilisers with trace elements that have been shown to subsequently accumulate in the soil and be taken up by plants, posing a danger to the environment and human health. Conventional characterisation methods necessary to ensure the quality of fertilisers and to comply with local regulations are costly, time consuming and sometimes not even accessible. Alternatively, using a wide range of unamended and intentionally amended fertilisers this study developed empirical calibrations for a portable handheld X-ray fluorescence (pXRF) spectrometer, determined the reliability for estimating the macro and micro nutrients and evaluated the use of the pXRF for the high-throughput detection of trace element contaminants in fertilisers. The models developed using pXRF for Mg, P, S, K, Ca, Mn, Fe, Zn and Mo had R2 values greater or equal to 0.97. These models also performed well on validation, with R2 values greater or equal to 0.97 (except for Fe, R2val = 0.55) and slope values ranging from 0.81 to 1.44. A second set of models were developed with a focus on trace elements in amended fertilisers. The R2 values of calibration for Co, Ni, As, Se, Cd and Pb were greater than or equal to 0.80. At concentrations up to 1000 mg kg-1, good validation statistics were also obtained; R2 values ranged from 0.97–0.99, except in one instance. The regression coefficients of the validation also had good prediction in the range of 0–100 mg kg-1 (R2 values were from 0.78–0.99), but not as well at lower concentrations up to 20 mg kg-1 (R2 values ranged from 0.10–0.99), especially for Cd. This study has demonstrated that pXRF can measure several major (P, Ca) and micro (Mn, Fe, Cu) nutrients, as well as trace elements and potential contaminants (Cr, Ni, As) in fertilisers with high accuracy and precision. The results obtained in this study is good, especially considering that loose powders were scanned for a maximum of 90 seconds without the use of a vacuum pump.

Characterization of the Obsidian Used in the Chipped Stone Industry in Kendale Hecala

Kendale Hecala is located on the Ambar River in the Upper Tigris Basin, province of Diyarbakır in Southeast Anatolia. Various raw materials, including obsidian, radiolarite, chert, jasper, chalcedony, and quartzite, were used in the lithic industry. Obsidian artefacts constitute an average of 64% of the chipped stone assemblage. Technological analysis reveals that obsidian was brought to the settlement as nodules and chipped into various tools at the settlement. Understanding the operational sequence of the lithic industry, chaîne opératoire, including the distribution of raw material from source to site, is important to demonstrate the socio-cultural organization of the settlement in Southeastern Anatolia during the Ubaid period. In order to identify source varieties, the obsidian artefacts uncovered from Ubaid layers of Kendale Hecala were analyzed by macro-observations, and the characterization of archaeological samples was performed using a handheld XRF. Multivariate analysis of the data indicates the use of obsidian from different resources at the settlement, including Nemrut Dağ, Bingöl B, and Group 3d.

In situ measurements using hand-held XRF spectrometers: a tutorial review

Hand-held XRF is described from a tutorial viewpoint suitable for users without extensive training in XRF methodology in order to raise awareness of issues in using the technique and improve the interpretation of hand-held XRF measurement results.

Pellet bells and bells from the Avar Period in the Hungarian National Museum

The Great Migration Period collection of the Hungarian National Museum houses more than 67 pellet bells and bells from the Avar Period, which are part of the research project ‘Metallic Idiophones between 800 BC and 800 AD in Central Europe’. They originate from 17 archaeological sites. The idiophones are presented within their find context and classified into types. Chemical analyses were carried out non-destructively by using a handheld XRF. The sounds of the original objects were recorded and analysed about their frequency ranges and psychoacoustic parameters. Several suggestions of the idiophones function complete the article. Ten textiles were analysed on the pellet bells, revealing some information on possible pieces of clothing and the positioning in the burial.

Analytical comparisons of handheld LIBS and XRF devices for rapid quantification of gallium in a plutonium surrogate matrix

Comparing two handheld elemental analyzers for potential use in plutonium manufacturing quality control.

Pharmacognostic Potentials of Dried Powdered Seeds of Traditional Medicinal Plant Usteria guineensis used for the Treatment of Typhoid Fever in Sierra Leone

Pharmacognostic potentials and mineral analysis was carried out on the of dried powdered seeds of traditional medicinal plant Usteria guineensis used for the treatment of Typhoid fever in Sierra Leone. The results indicate the colour of the dried powdered seeds of the plant to be light yellow with fruit odour and had a bitter taste indicating that the powdered plant material contains alkaloids. The following reagents 1M NaOH (aq), 1M NaOH (alc.), Ammonia, 50% HCl, and 50% HNO3 exhibited fluorescent activities when added to portions of the dried powdered seeds of U. guineensis and viewed under UV Lamp. The plant organ investigated contained high contents of carbohydrates, alkaloids, flavonoids, proteins sterols/terpenes and tannins, saponins in the Ethanolic, methanol and aqueous extract during phytochemical screening. The detection of the above secondary plant metabolites supports the use of the plant in traditional medicine. Elemental analysis of the dried powdered seeds of U. guineensis using Niton XL3t GOLDD + Hand held X-ray Fluorescence (Thermo Fisher). The spectrum acquisition time was 480sec for the sample and the dead time was around 50% a total of fifteen elements (K, Ca, Mg, Al, Ti, V, Mn, Fe, Cu, Zn, Rb, Sr, Zr, Mo, and Sc) were determined in the dried powdered seeds of Usteria guineensis plant by using EDXRF. The results indicate that the plant organ investigated contained K (29458 ± 163 ppm), Ca (3702 ± 54.00 ppm), Mg (5528 ± 1223 ppm), Al (1389 ± 168 ppm) and Fe (167.11 ± 9.20 ppm). The other elements present in smaller quantities were Ti (64 ± 12.00 ppm), Sr (4.74 ± 0.40 ppm), Zn (56.65 ±2.46 ppm), Rb (47.34 ± 1.00 ppm), Zr (20.73 ± 0.67 ppm), and Mo (6.94 ± 0.74 ppm). The elements Sc, Mn, Cu and V were out of limit of detection of the equipment. The above elements detected are essential components of biological structures that mediate vital effect on and play a key role in a variety of the biochemical processes necessary for life.

New results on horse trappings from the Hunnic-period Carpathian Basin based on non-destructive archaeometric analyses

Objects manufactured from pressed gold, gilded silver or copper alloy plates are characteristic assemblages from the Late Hunnic period (5th century AD, 420/430). In this study, horse trappings that belong to the ‘pressed gold plate horizon’ from three archaeological sites in the Carpathian Basin (Léva, Nyíregyháza-Oros and Pécsüszög) were analysed non-destructively by using a handheld X-ray fluorescence spectrometer. The main aims were to determine the chemical composition and the gilding technique used, and to attempt to prove whether the groups in an assemblage are from the same set. The results of the chemical analyses give us the opportunity to confirm whether damaged or presumably lost objects of an assemblage were replaced or repaired. According to the results obtained, the objects were manufactured from gold (Pécsüszög), gilded silver (Nyíregyháza-Oros) or gilded unalloyed copper plates (Léva). Later, replacements can be distinguished based on their chemical composition and manufacturing quality. Two types of gilding were observed: fire gilding with the presence of mercury (Léva), and leaf gilding (Nyíregyháza- Oros).