Viorica Vasilache

Assessment of cleaning effectiveness for new ecological systems on ancient tempera icon by complementary microscopy techniques

The study presents an old icon painted in egg tempera on lime wood, with a poor conservation condition and clogged dirt deposits. The icon is attributed to an anonymous painter of XIXth century and to the neo‐classical style of painting. The painting layer was done with only a hand full of pigments, earth colors that were often used in painting the icons from XVIIth to XIXth century in Eastern Europe, that have Byzantine influences. Taking into consideration the nature and the structure of the materials from the upper layers of the painting, affected by deposits of dirt over time, a series of cleaning recipes were studied, using the so called cleaning tests with compatible mixtures of different juices and infusion from indigenes plants, that were freshly done and odorless. A low alkaline 95% ethyl alcohol solution, combined with a few drops of ammoniac 25%, was used as a reference system, due to its compatibility with the greasy deposits found on the polychrome layer and on the wood. The cleaning capacity of the new systems used, in comparison with the standard solution, was analyzed through modern analytical methods of evaluating the degree of cleaning, more exactly by means of visible and UV reflectography, CIE L*a*b* colorimetry by reflection assisted by SEM‐EDX and IR spectroscopy. Microsc. Res. Tech. 77:1060–1070, 2014.

Study of the atypical formations in the corrosion bulks of an ancient bronze shield, by optical and electron microscopy

This article presents the atypical formations in the structure of the corrosion crust and in the partially mineralized metallic core, which resulted during the underground stay of a bronze shield, dated between the 1st century B.C. and the 1st century A.D. For our study, we choose a representative fragment from the rim of the shield, which was analyzed by optical microscopy and by electron microscopy coupled with energy‐dispersive X‐ray spectroscopy, to study its morphology, its composition, and the location of chemical compounds on the surface and inside the bulk formed during the underground stay, by processes of chemical and physical alteration, assisted by contamination with structural elements from the site. Those processes, by monolithization and mineralization formed a series of structures consisting of congruent elements and phases with a complex composition. Those formations, defined as surface effects generated by exogenous factors and endogenous factors inside the bulk, are frequently found in ancient bronze objects (such as the exterior flat mole formations and the Liesegang effect in the stratigraphic structure of the bulk). Some of those structures have atypical characteristics as regards their structure, composition, and formation mechanism, which may be used in archeometry. Moreover, that includes the object in the category of special cases, in terms of artifact evolution during underground stay and of the atypical formations resulted from the action of pedological and environmental factors. Microsc. Res. Tech. 2012.

Influence of archaeological environment factors in alteration processes of copper alloy artifacts

The article presents the experimental results obtained by combining noninvasive techniques (OM, SEM/EDX, XRF) to analyze three artifacts made of copper alloys discovered in a inhumation tomb (2) and in the soil profile (1) in archaeological sites from Neamt County Romania. To uncover the mechanism of alteration thereof during their longtime underground stay in specific chemical conditions and under the influence of other pedological factors, the corrosion products must be identified. The excess of the chloride ion, from burial site, disturbs the Liesegang effect, transforming the bulk in a stratified sponge structure with chlorapatite and hydroxyapatite. Some of the compounds from primary and secondary patina can be found on the surface of the bulk, as color stains. The presence of alloy components (Cu, Sn, Pb, Zn, Fe, etc.) and of the underground contamination components, allowed us to establish the origin of the ore, the manufacture technology and we identified other materials which affected the artifacts after abandonment. Microsc. Res. Tech., 2012.

Colour change evaluation on UV radiation exposure for Păun-Repedea calcareous geomaterial

When talking about the preservation treatments that can be applied to natural stones used in different constructions, the surface hydrophobization plays an important part, especially when referring to porous surfaces like the calcareous oolithic stones specific to Repedea area, Iasi County, Romania. The present paper presents a method that evaluates the hydrophobization efficiency of two types of pellicles, involving UV artificial ageing and colorimetric analysis of the treated surfaces. The evaluation was done through continuous colorimetric monitoring and by comparing the evolution of the chromatic modifications of the two treated surfaces with the original colorimetric values and with the witness area, which was exposed to UV radiations under the same conditions, but left chemical untreated. The techniques used during this experiment were: CIE L*a*b* colorimetry, OM, SEM-EDX, UV radiation exposure and Spectrum Irradiance Measurement.

Study of an Old Coin Set Using Nondistructive Techniques

The paper presents the chemical composition and mineralogical distribution of the corrosion crust, more so the chemical composition and the texture of the metallic core on three silver coins dating from the seventeenth century, discovered in various tombs in the necropolis belonging to the former Stratenia Church from Iasi. These were examined by the corroboration of optical microscopy, electron microscopy coupled with X-ray diffraction (SEM-EDX) and the micro-FTIR techniques. The data allowed to establish the main alloy and of the evolutionary contexts during the laying period, based on the texture of the metallic core and on the layout of corrosion products.

Establishing the archaeo‐metallurgic ornamentation process of an axe from the bronze age by OM, SEM‐EDX, and Micro‐FTIR

Our article presents the results of the analyses we performed by corroborating the Optical Microscopy, Scanning Electron Microscopy, Energy Dispersive Xray Analysis and micro Fourier Transformed InfraRed Analysis techniques to identify the archaeo‐metallurgic casting and ornamentation procedure of a decorated disk‐butted axe, which was discovered recently east of the Carpathian mountains, in the Moldavian Plateau. There are few known axes of that type found (A1, according to the usual typologies), as they are specific to the Middle Bronze Age period west of the Carpathians—the Wietenberg, Suciu de Sus, and Otomani‐Füzesabony cultures. The experimental data on the item under study revealed the fact that after casting it in molds made from porous silicone‐based stone, the object was coated with a thin layer, by immersing it in a lightly fusible tin alloy, whose main alloy component was copper and arsenic and iron as secondary components. After refining the shiny white layer, they applied a beautiful decoration pattern made by incision and engraving. This battle axe was an indication of higher status, such items usually being owned by community leaders. This important fact proves that the ancient metallurgic craftsmen were able to elaborate and manufacture various alloys from which they made beautiful objects and it also offers a new insight into the social and symbolic function of certain antique bronze items. Microsc. Res. Tech. 77:918–927, 2014.

Approaching on Colorimetric Change of Porous Calcareous Rocks Exposed in Urban Environmental Conditions from Iasi – Romania

According to the scientific literature, the pollution phenomenon is strongly related by the urban activity from the last decades, with direct effects on the state of conservation of the stone constructions also. This paper presents a preliminary study on the colorimetric evolution of the lithic surfaces exposed under strongly traffic influence from the urban microclimate conditions. The analysed lithic surfaces are similar with the building stone from the structure of an historical monument (from 19th century), such as the Stone Bridge in Iasi-Romania, located in the immediate vicinity of the roadside loop with the same name. The colour change monitoring for the above-mentioned geomaterials aims at anticipating the effects of postponing the decongestion of car traffic and implicitly initiating the assessment of the effects of pollution over this historic monument, which is in an advanced state of deterioration and degradation.

Modern Procedures Used in Cleaning Old, Illegibly and Blackened Icons

Abstract In order to restore the original aesthetic aspect, to improve the state of the age patina and of the gold halo, similar processes are required. The cleaning process is one of the most important aspects for an artwork and is considering a series of deteriorations and degradations, like dirt deposits (clogged or unclogged) opalescent varnish, colors blackening, burns, blisters, gaps (missing ground, painting layer or varnish). This step in the restoration process includes physical and mechanical proceedings like dusting (with a vacuum), brushing (with a brush), scraping (with a scalpel), removal or polishing etc. The scalpel and the milling process are rough unconventional means that are used only in exceptional cases. The wet cleaning of dirt includes classic washing processes, with water or other complex systems of organic solvents (emollients, surface additives or surfactants, mixtures of solvents). Cleaning the clogged dirt deposits with unconventional methods can be done by means of electronic laser, ion and thermal exchange or ultrasounds. Laser cleaning is often used in removing unwanted dirt deposits from different layers of the art piece. A lot of attention goes towards the controlled elimination of the exterior protection layer (varnish), which can be photo- degraded and oxidized by atmospheric exposure. Visual analysis, with enlargers (OM, SEM, AFM etc.) combined with transmission or penetration techniques (radiography, endoscopy, X-ray diffraction etc.) provides information on the superficial structures of the art work. In order to determine the modifications of the desiccant oils, SEM was used to observed the changes in the morphology of the oil painting layers. Gas chromatography/mass spectrometry (GC/MS) can be used to detrmine detergent residues on the painting layer.

The Study of Ornamental Gildings in Old Tempera Icons from the XVIII-th Century

The paper presents the study of old ornamentation techniques used into making of two icons from the XVIII-th century, part of the heritage of Tazlau monastery, Neamt County. In order to do this, the materials used to create the polychrome layers and their current conservation state was analyzed. The data obtained by investigating the two mentioned elements have allowed for the identification of different traditional techniques, used for ornamental gilding. Optical microscopy (OM) and Scanning Electron Microscope coupled with Energy Dispersive X-ray spectroscopy (SEM-EDX) were employed in the analyses. The archaeometrical characteristics of the pigments and binders, collaborated with the aesthetic analyses, allowed the dating of the two icons for the end of the XVIII-th century.

Impact on Surface Treatment of Hydrophobic Consolidation Terracotta Ornaments

During the consolidation and rehabilitation interventions of George RaduMelidon City Library Roman, Neamţ County, a series of architectural terracotta decorations, manufactured in the second half of the century XIX, have been identified and cataloged. The current state of these decorations, made from geomaterials, requires the establishment of a technical solution which will be used to preserve, to strengthen the color, the aesthetic surface and the chromatic reintegration. Thus, the paper presents the study of four current commercial chemicals products, part of the additives hydrophobic/waterproofing group. One of the products is a water based emulsion, while the other three are organic based solvents. This study was required in order to develop an optimal treatment to preserve the old terracotta from facade of building already mentioned. The technical features that these products have in common are sealing and waterproofing by superficial coating, with an average penetration and restoration of chromatic aspect, as close to the original. CIE L*a*b* colorimetry, optical microscopy and the measure of humidity (reversible water content and related chemical) were implemented in the study of optimization of pellicle dispersion systems based on the four chemicals.