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During the last restoration campaign of the Baptistery of San Giovanni in Florence (Italy), the assessment of the state of conservation of external surfaces was performed, with a multi-analytical approach, in order to support the conservation and restoration treatments. Black crusts, red staining, sulphation, and organic patinas were identified. Moreover, a complete characterization of marble cladding, bricks, and mortars was carried out. A geochemical and minero-petrographic approach was used in order to classify and assess the provenance of marbles, and define raw materials and technologies of the production for bricks and mortars. Provenances from Italy (Carrara and Lasa marbles) and from Greece (Hymettus and Pentelicum marbles) were identified and attributed to different construction phases, restoration interventions, and re-use of ancient materials. For mortars, the obtained data suggested the use of local materials and traditional technologies for the production. Overall, two different minero-petrographic typologies were identified for the analyzed bricks. [ABSTRACT FROM AUTHOR]

This study attempts to demonstrate how Greek builders exploited their geological environment during the Archaic to Hellenistic periods. Four major sites in the eastern part of the Gulf of Corinth are compared: the old city of Corinth, the sanctuary of Poseidon at Isthmia, ancient Sikyon and the Heraeum at Perachora. Ancient builders utilised primary topographic features and natural resources to their advantage, thus reducing costs. They preferred local low-density stones sourced from the more recent Corinth syn-rift deposits (calcarenite, oolitic grainstone, sandstones, stromatolites and conglomerates), rather than the pre-rift Mesozoic carbonates. These local stones representmore than 90% of the volume employed for public construction. Greek builders also imported allochthonous high-porosity limestones for their temples. Hard stones, such as marbles, do not appear to have been attractive to ancient builders at any of the studied sites. [ABSTRACT FROM AUTHOR]

The aim of this study is to assign the provenance of Roman marble statues and assess their condition in order to use this information as a guideline for their future conservation treatments. Several analytical methods were applied to investigate the provenance of the statues including petrography, X-ray diffraction, and mass spectrometry. The deterioration level of the statues was assessed by non-destructive ultrasonic velocity measurements. The provenance investigation showed that four statues were most probably made of the dolomitic marble quarried from Thasos Island, Greece and one statue was made of the Proconnesus marble quarried from Marmara Island, Turkey. The condition assessment study revealed that the statutes are still in a good condition, although they exhibit weathering in the form of increasing porosity. Consequently, suitable conservation measures and recommendations for preserving the marble statues and preventing future damage were proposed. In general, the ultrasonic technique proved to be effective for assessing marble condition and identifying and prioritizing required conservation work in a fast, reliable, and non-destructive way. [ABSTRACT FROM AUTHOR]

This paper presents for the first time chemical data on the ancient (Antiquity period) marble quarries of Delos Island and some architectural marbles from its famous and exceptionally well‐preserved archaeological site. Delos geological substratum is mostly composed of granite, including very few decametric marble enclaves. However, ancient Delian architecture is dominated by gneiss and marbles. A large quantity of marble had thus to be imported from neighbouring Cycladic Islands and continental Greece. Their provenances remain mostly unknown. Several analytical methods have been developed in archaeometry for years to determine the origin of marbles, but they are generally destructive. This paper reports a methodology based on a hand‐held portable X‐ray fluorescence (pXRF) analyser to detect major and trace elements often used in provenance studies. Drawbacks of using those elements for marble provenance and analytical limitations attached to portable instruments were frequently discussed. Here the usefulness of pXRF for marble provenance research was tested in association with principal component analysis (PCA). Two artefacts of presumed Delian origin were selected and the results showed that one of them came undoubtedly from a Delian quarry while the other one was not of local origin. This protocol appeared to be a powerful tool when conventional destructive analyses are precluded. [ABSTRACT FROM AUTHOR]

The exploitation of dimension stones, especially marble, has always been important for Greek economy. In the dimension stone market, granite and schist are also included. However, marble is by far the most important product of the dimension stone market of Greece. An attempt to highlight the trends of the last decade in the market of dimension stones in Greece is attempted. Several factors potentially affecting the demand are also assessed. Domestic demand for dimension stones seems to increase, but this is applied more to the general constructions sector rather than in private dwellings. The production and exports of marble and schist follow increasing patterns since 2011. The domestic market of granite is more complicated, due to the fact that there is no systematic exploitation of granite in Greece, even though the demand and therefore the imports increase steeply since 2017. [ABSTRACT FROM AUTHOR]

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The clausiliid Carinigera buresi has a distribution that, considering its low vagility, is enigmatically disjunct. Carinigera buresi pharsalica occurs in Thessaly in central Greece, over 200 km outside the main range of C. buresi in NE Greece – SW Bulgaria. This range disjunction has led to the hypothesis that in antiquity the ancestors of C. buresi pharsalica were transported by the marble trade from NE Greece to Thessaly. To explore this hypothesis, we included samples from the NE Greek island of Thasos (the only area within the range of C. buresi from which marble was widely transported in antiquity) in a time-calibrated molecular phylogeny of C. buresi. Maximum likelihood (GARLI) and time-calibrated Bayesian (BEAST) analyses of mitochondrial cytochrome c oxidase subunit I (COI) from samples collected throughout the range of C. buresi indicate that the ancestral C. buresi pharsalica COI lineage reached Thessaly not from Thasos, but from the NE Greek mainland. This happened between 1,740 and 83,000 yr BP according to the BEAST analyses. Although this time interval does not entirely pre-date the earliest phase of marble transport in the region, we consider this mode of dispersal unlikely for two reasons: (1) our data show that C. buresi pharsalica must be older than estimated on the basis of geological calibration points; (2) our findings indicate that the dispersal event that brought C. buresi pharsalica to Thessaly did not follow ancient marble transport routes. We suggest dispersal via floating objects or aerial dispersal by birds as alternative hypotheses to dispersal by the historic marble trade. Unexpectedly, our phylogenetic analyses also showed the COI haplotype of C. buresi from the city of Kavala to be nested among COI haplotypes from northern Thasos. This suggests possible human-aided dispersal of C. buresi from Thasos to Kavala. [ABSTRACT FROM AUTHOR]

Laser scanning has proven useful in the stability assessment of underground openings. High accuracy points are used to generate 3D surface models to evaluate their stability by assessing rockmass structural features. A series of scans obtained from underground ancient quarries in Paros Island were processed. The structural analysis of the openings was complemented by field observations and measurements, serving as input parameters for numerical software used to evaluate the potential failure mechanisms and overall stability. Blocks with a higher risk of detaching are encountered mostly at tunnel portals where support is required to secure unstable blocks to preserve this geotope. [ABSTRACT FROM AUTHOR]

In this work, Bacillus pumilus ACA-DC 4061 was selected for its increased capability for biomineralization on marble, under different nutrient media concentrations and temperature conditions. The optimum conditions for the CaCO 3 bacterially-induced precipitation were determined with the aid of testing based on the Design of Experiments (DoE). Biomineral (vaterite) precipitation was favored in both the temperatures (25 and 30 °C) investigated. Stone loss rate was reduced when the samples were subjected to sonication. Thin sections of the substrate confirmed that vaterite was able to adhere onto the surface. Finally, under non-sterile conditions mimicking an in situ application, B . pumilus ACA-DC 4061 formed a fine layer of calcium carbonate. Therefore, this microorganism showed that vaterite formation may consistently occur under specific conditions and could prove useful as a candidate for on-site applications for stone conservation. [ABSTRACT FROM AUTHOR]

The restoration of destroyed connections of epistyles joined together by means of metallic connectors is among the most difficult problems encountered by scientists working for the conservation/restoration of monuments made of marble. The complexity of the geometry and the interaction of three completely different materials (metal-filling material-marble) constituting the connection render the study (either experimental or analytic) extremely complicated. In this direction a numerical analysis is presented here in order to deeply understand the response of a typical ancient connection subjected to axial loads as well as to quantify the influence of some geometric parameters on its response. The parameters studied include the length of the connector, the width of its flanges, the depth of the groove (mortise), the existence or not of relieving space and the filling material’s volume. The numerical model was calibrated and validated according to the results of an earlier experimental study realized on the worksite of the Parthenon Temple. It was concluded that the interventions required to relieve the stress field by changing the size of the connector are disproportional to the respective positive effect on the response of the connection. Moreover it was proved that the most beneficial parameter is the relieving space. [ABSTRACT FROM PUBLISHER]

The “marble” Portasanta from Caldana (Grosseto, Italy) takes its name from the strict resemblance to the ancient Marmor Chium (also this called Portasanta ) coming from the island of Chios in Greece. In this work, a complete characterization of the Italian Portasanta was made: chemical (X-ray fluorescence and isotopic analyses), mineralogical (X-ray diffraction on the bulk sample and on insoluble residue after acid attack), physical (water accessible porosity and imbibition coefficients), petrographical (optical microscopy) and mechanical (compressive strength test) analyses have been carried out in order to obtain a better distinction between Italian and Greek “marble”, sometimes mistaken. The Portasanta from Caldana (Italy) was quarried surely in the sixteenth century, but a possible use of this material during Roman time is still in doubt. The study of samples from some Tuscan archaeological sites (Torraccia di Chiusi, Siena and Roselle, Grosseto) allows us to confirm the use of Portasanta from Chios for the Torraccia site and that of Caldana for Roselle. [ABSTRACT FROM AUTHOR]

Dolomitic marble from the Thassos Island in Greece consists of the Dol ± Cal + Tr ± Tlc + Srp retrograde mineral assemblage. The retrograde phase of metamorphism of the studied marble took place under the amphibolite facies conditions. The average calculated temperature of recrystalization of calcite reached 496 ± 9°C, calculated according to the first calibration. Using the second calibration, the temperature range was estimated at 517 - 529 °C for a given pressure interval 300 - 350 MPa. The temperature 464 ± 27°C at a pressure of 350 ± 1 MPa was calculated from the retrograde univariant reactions intercept using THERMOCALC ver. 3.33. [ABSTRACT FROM AUTHOR]

The Cycladic blueschist belt, Greece, is mostly submerged below sea level and regional correlations are difficult to establish. Marbles are widespread within the belt and locally used as marker horizons to subdivide monotonous schist sequences. However, owing to the lack of distinctive petrographic characteristics, the marbles have not been used for island-to-island correlations. This study aims to investigate the potential of Sr-, C- and O-isotope compositions of marbles as a tool for unravelling the litho- and/or tectonostratigraphic relationships across the Cycladic islands, and as a proxy for the time of sediment formation. For this purpose, we have studied metamorphic carbonate rocks from the islands of Tinos, Andros, Syros, Sifnos and Naxos. Identical 87Sr/86Sr values for certain marble horizons occurring on Tinos, Andros and Sifnos are interpreted to document coeval regional carbonate precipitation. The 87Sr/86Sr values of the apparently least altered samples intersect the seawater curve multiple times within the most likely time interval of original carbonate precipitation (< 240 Ma; as indicated by previously published ion probe U–Pb zircon data) and thus an unequivocal age assignment is not possible. Very broad temporal correlations are possible, but more subtle distinctions are not feasible. On Andros, the overlapping Sr-isotope values of marbles representing the lowest and highest parts of the metamorphic succession are in accordance with a model suggesting isoclinal folding or thrusting of a single horizon, or very fast sedimentation. In contrast, distinct 87Sr/86Sr values for samples from Tinos, representing different levels of the metamorphic succession, suggest that these rocks represent a temporal succession and not the tectonic repetition of a single horizon. Based on Sr-, O- and C-isotope characteristics alone the time equivalence of marbles occurring on different islands could not be documented unambiguously. However, by using various combinations of these parameters, some occurrences can be discriminated from the overall sample population. The new data further accentuate the general potential of coupled Sr-, C- and O-isotope characteristics for identification of archaeological provenance and complement existing datasets for Aegean marbles. [ABSTRACT FROM AUTHOR]

Abstract: Microboudinage structures developed within glaucophane are found in the calcite matrix of blueschist-facies impure marbles from Syros, Greece. The presence of these structures enables the successful application of the microboudin method for palaeodifferential stress analysis, which was originally developed for rocks with a quartzose matrix. Application of the microboudin method reveals that differential stress increased during exhumation of the marble; the estimated maximum palaeodifferential stress values are approximately 9–15 MPa, an order of magnitude lower than the values estimated using the calcite-twin palaeopiezometer. This discrepancy reflects the fact that the two methods assess differential stress at different stages in the deformation history. Differential stresses in the Syros samples estimated using three existing equations for grain-size palaeopiezometry show a high degree of scatter, and no reliable results were obtained by a comparison between the results of the microboudin method and grain-size palaeopiezometry. [ABSTRACT FROM AUTHOR]

Abstract: The response of either intact or fractured and restored marble architraves under bending is the object of the present paper. The study is motivated by the needs of the scientists, working for the extensive restoration program of the Parthenon Temple on the Acropolis of Athens, for an in-depth knowledge of the stress and strain fields developed in restored structural elements when they are placed back in their initial position. A recently introduced procedure is employed for the calculation of the reinforcement required for the restoration. A numerical model with contact elements is developed for the simulation of a prismatic architrave (epistyle) resting on marble supports (capitals, abacuses) and subjected to various types of bending. The points most prone to fail are located for both the intact and the restored architraves and it is concluded that the reproduction of actual bending conditions in the laboratory may lead to erroneous conclusions if the results are not interpreted carefully taking into account the exact way of applying the external loads. The most important findings of the numerical analysis are compared to those of previous experimental studies and are juxtaposed to the conclusions drawn from the study of the present state of the monument. [Copyright &y& Elsevier]

The provenance question of the marbles used for making the sarcophagi of local production of Thessaloniki in the Roman period had been posed by archaeologists in the past. The hypothesis was that the material came mainly from the quarries of Thassos Island. This paper presents the scientific analysis of 23 characteristic samples from selected sarcophagi at the Museum of Thessaloniki, using three different techniques: electron paramagnetic resonance (EPR) spectroscopy, stable isotope analysis and maximum grain size measurements, plus in-situ examination. New combinations of parameters were used in order to resolve fully the provenance of all samples. The results showed that the vast majority of the objects were indeed made in Thassian marble but from three different quarries, namely Vathy/Saliara (dolomitic marble), Aliki (calcitic marble) and Acropolis/Phanari (calcitic marble). The calcitic marbles from Aliki and to a lesser degree from Acropolis/Phanari are met in all the basic types of sarcophagi (framed type, plain type, garland sarcophagi). The use of the better quality and snow-white dolomitic marble from Vathy/Saliara quarries is relatively restricted and is often found in works that are above the average regarding the quality of their workmanship. In addition, two sarcophagi were made in Pentlelic marble and one in Proconnesian. The scientific analysis results provide a good confirmation of the archaeological estimates and, furthermore, the conclusions constitute henceforth a secure basis for the study of the entire sculptured works of Thessaloniki. [ABSTRACT FROM AUTHOR]

It is known that in historical buildings as well as new buildings, facade claddings consisting of marble panels, are prone to damage patterns such as softening, crack formation, and bowing. The degree of damage is apparently dependent on the location of the building, the external climatic conditions, and the type of fastening of the facade panels. In this article, it is examined by means of nonstationary thermal simulation, to which extent the temperature fields, which develop in the facade panel, have an effect on the damage of the panel. It is shown that the diurnal and annual amplitude of the panel temperature induced by solar flux, external air temperature fluctuations, and long-wave input radiation and irradiation have a substantial influence on the damage process. On the example of the simulation of the thermal behavior of a facade panel for the building locations in Athens, Greece, Vienna, Austria, and Helsinki, Finland, it is shown that the observed increase of the susceptibility of marble facades to damages can be explained with the increase of the geographical latitude through the differences in the external climatic conditions. It is strongly recommended that architects and restorers install specific marble facade panels (like carrara marble) in close thermal contact with the wall behind, since this reduces the susceptibility of the facade to damage. [ABSTRACT FROM AUTHOR]

The mechanical behaviour of marble architraves, restored with titanium bars and suitable cementitious material, is studied with the aid of the finite-element method. The study was motivated by the needs of the conservation project in progress on the Parthenon Temple of the Acropolis of Athens. A realistic numerical model was created taking into account the exact geometry of the threaded bars as well as the exact mechanical properties of the materials involved. The architrave was considered as a prismatic beam of rectangular cross section, centrally fractured and restored with one threaded titanium bar. The bar was inserted in a hole of slightly greater diameter drilled in the member and filled with suitable cementitious material. In this way, a sequence of three materials appears (marble–cement–titanium) giving birth to two interfaces (marble–cement and cement–titanium). Emphasis was given to the influence of the cement layer on the stress and strain fields. The cement was modelled as either linear or bilinear material and the analysis indicated the crucial role of this layer for the drastic reduction in the strain discontinuities. [ABSTRACT FROM AUTHOR]

Flutes are longitudinal grooves sculptured on the perimeter of the columns of ancient Greek or Roman temples. It is widely accepted that flutes were sculptured mainly for aesthetic reasons. However, strong indications exist that the presence of flutes somehow changes the overall mechanical behaviour of the column. This could be expected due to the singularities introduced by the imposed abrupt change in the boundary conditions of the specimen, where the friction boundary of the base meets the free boundary of the lateral surface. Following the previous line of thought it was decided to check this hypothesis by studying the mechanical behaviour of a typical drum of a column of the Parthenon Temple of the Acropolis of Athens. These columns have 20 flutes and their shape is accurately described as an arc of an ellipse. The study was carried out both numerically and experimentally. The parameters studied included the number and the shape of the flutes as well as the type of loading. It was concluded that the presence of flutes significantly modifies the stress and strain fields developed especially under torsion. In addition, the fluted drum appeared to be stiffer in comparison with the non-fluted one. [ABSTRACT FROM AUTHOR]

Abstract: This study allowed the identification of the main physicochemical characteristics of deterioration of the materials used in the construction of Greek ancient statues in order to plan a correct methodology of restoration. The method of Reversed-Flow Inverse Gas Chromatography is appropriate to investigate the influence of air pollutants on authentic pieces from the Greek Archaeological Museum of Kavala, near Salonica. Six local physicochemical quantities which refer to the influence of one or two pollutants (synergistic effect) were determined for each system. These quantities answer the question “when, why and how materials of cultural heritage are attacked”. [Copyright &y& Elsevier]

A description is provided of the contribution of time-resolved analysis in understanding adsorption phenomena and its contribution to an examination of the overall degradation mechanism of authentic marble pieces brought about by air pollution. As a consequence, a scientific answer has been provided to the question "how are materials of cultural heritage affected by air pollution?" The use of reversed-flow inverse gas chromatography (RF-IGC) has allowed the determination of important local physicochemical quantities relating to the influence of three light hydrocarbons, either in the presence or absence of sulphur dioxide. A detailed analysis of the results as well as a correlation study is given. [ABSTRACT FROM AUTHOR]

Abstract: In this work, digital processing of scanning-electron-microscopy images utilized to assess cleaning interventions applied on the Pentelic marble surfaces of the National Archaeological Museum and National Library in Athens, Greece. Beside mineralogical and chemical characterization that took place by scanning-electron-microscopy with Energy Dispersive X-ray Spectroscopy, the image-analysis program EDGE was applied for estimating three evaluation indexes of the marble micro-structure. The EDGE program was developed by the U.S. Geological Survey for the evaluation of cleaning interventions applied on Philadelphia City Hall. This computer program analyzes scanning-electron-microscopy images of stone specimens cut in cross-section for measuring the fractal dimension of the exposed surfaces, the stone near-surface fracture density, the shape factor (a surface roughness factor) and the friability index which represents the physico-chemical and physico-mechanical stability of the stone surface. The results indicated that the evaluation of the marble surface micro-structure before and after cleaning is achieved by the suggested indexes, while the performance of cleaning interventions on the marble surfaces can be assessed. [Copyright &y& Elsevier]

The interaction of Greek dolomitic marble (from Thassos island, northern Greece) with Co2+, Cd2+, Pb2+ and Cr3+ containing aqueous solutions was studied by characterizing the surface of the solid experimental samples, using a combination of spectroscopic, microscopic, and diffraction techniques (RBS, XPS, SEM-EDS, FT-IR, powder-XRD). The obtained results indicated a considerable Cd2+ and Co2+ sorption on the dissolved surface of the carbonate substrate, whereas, under the same experimental conditions, the Pb2+ and Cr3+ interaction is more intense leading to extended overgrowth of crystalline Pb2+ carbonates and massive surface precipitation of amorphous Cr3+ hydroxide/oxyhydroxide. [ABSTRACT FROM AUTHOR]

The ultra-high-pressure (UHP) Kimi complex (uppermost eastern Rhodope Mountains) is a tectonic mixture of crustal and mantle derived associations. Pressure–temperature (P–T) paths and microtextural and geochronological data reveal that crustal and mantle parts juxtaposed against each other at a depth corresponding to ~15 kbar (1 kbar = 100 MPa) had separate ascend histories. The crustal rocks comprise amphibolitised eclogites, orthogneisses, marbles, and migmatitic pelitic gneisses. The latter document UHP metamorphism within the dehydration-melting range of pelitic gneisses, with maximum P–T conditions of >45 kbar at ~1000 °C, as determined by diamond inclusions in garnet and rutile needle exsolutions in Na-bearing garnet. Decompression was combined with only little cooling before 15 kbar, followed by more significant cooling between 15 and 10 kbar. This P–T path probably reflects ascent of UHP rocks within a subduction channel, followed by accretion in the lower crust of a thickened wedge. Although the first ascend phase was probably rapid, the overall time span for UHP metamorphism and final exhumation may have extended over more than 70 Ma. A U–Pb sensitive high-resolution ion microprobe (SHRIMP) age on zircons of ±149 Ma was suggested to date the UHP metamorphism, whereas Rb–Sr white mica and U–Pb zircon ages from syn-shearing pegmatites of ±65 Ma constrain medium- to low-grade shearing and final exhumation of UHP rocks. Mantle parts consisting of spinel–garnet metaperidotites and garnet pyroxenites reached maximum P–T conditions in the garnet-peridotite field at T > 1200 °C and P > 25 kbar. This was associated with plastic flow and followed by severe near isothermal cooling to T < 800 °C at 15 kbar and static annealing. A garnet–clinopyroxene whole-rock Sm–Nd age from a garnet pyroxenite of ±119 Ma probably reflects the age of metamorphic mantle processes (static annealing following the high P/high T strain episode), rather than constraining the age of UHP metamorphism. [ABSTRACT FROM AUTHOR]

Dolomitic marbles from the Organi and Pandrosos areas of the ultrahigh-pressure (UHP) metamorphic Kimi complex in East Rhodope, N.E. Greece have the mineral assemblage: Cal + Dol + Ol + Phl ± Di ± Hbl ± Spl ± Ti–Chu + retrograde Srp and Chl. Several generations of calcite and dolomite with variable composition and texture represent different stages of the P– T evolution: The first stage is represented by matrix dolomite ( ${\rm X}_{\rm MgCO_3}$ = 0.48) and relic domains of homogenous composition in matrix calcite ( ${\rm X}_{\rm MgCO_3}$ = 0.11–0.13); the second stage is evident from precipitation of lath-shaped and vermicular dolomite in matrix calcite. The third stage is represented by veinlets of almost pure CaCO3 and domainal replacement of prior calcite by nearly pure CaCO3 + Ca-rich dolomite ( ${\rm X}_{\rm MgCO_3}$ = 0.34–0.43). Matrix dolomite adjacent to CaCO3 veinlets also becomes Ca-rich ( ${\rm X}_{\rm MgCO_3}$ = 0.42). In fact, Ca-rich dolomites with ${\rm X}_{\rm MgCO_3}$ in the range of 0.40–0.34 are reported for the first time from metamorphic marbles. Coexisting Ca-rich dolomite and Mg-poor calcite cannot be explained by the calcite-dolomite miscibility gap. This assemblage rather suggests that Mg-poor calcite was aragonite originally, which formed together with Ca-rich dolomite according to the reaction Mg–Cal → Arg + Dol (1) at ultrahigh pressures and temperatures above at least 850 °C, when dolomite becomes disordered and incorporates more Ca than coexisting aragonite does in terms of Mg. The simplest explanation of these observations probably is to suggest two metamorphic events: The first one represented by relic matrix carbonates at relatively low to moderate pressures and temperatures of ca. 750 °C, and the second one limited by the minimum temperatures for dolomite disorder (ca. 850 °C) and in the aragonite + dolomite stability field, i.e. at a minimum pressure of 3 GPa and, if the presence of diamond-bearing metapelites nearby is considered, at conditions of at least 850 °C and 4.3 GPa in the diamond stability field. As there is hardly any back-reaction of Ca-rich dolomite + Mg-poor calcite to Mg-rich calcite, peak temperatures remained below the reaction (1) and the exhumation path probably crossed the aragonite-calcite transition at much lower than peak temperature. Cooling and decompression must have both occurred extremely fast in order for the µm-sized Ca-rich dolomite textures to be preserved. An alternative explanation of the formation of “UHP”-textures and compositions is by a fluid influx that not only caused serpentinisation and chloritisation of silicates but also Mg-leaching from carbonates, particularly from Mg-rich calcite and its fine grained dolomite-precipitates, thus transforming them into Mg-poor calcite + Ca-rich dolomite. [ABSTRACT FROM AUTHOR]

For many years the marble extraction sector of the Greek mining industry has been in conflict with the public, especially in terms of rehabilitation of marble quarry sites. One of the main reasons for that is that the marble extraction sector has been unable to adjust to the existing legislative guidelines for the rehabilitation, such as extensive backfilling and re-vegetation. In the majority of cases these methods fail due to erosion of the backfill soil and adverse climatic conditions. As a result the number of abandoned marble quarry sites is continuously increasing. The present paper suggests a different approach regarding the rehabilitation of marble quarries. More specifically, the paper questions the applicability, the effectiveness, and the social usefulness of the above-mentioned guidelines and suggests the establishment of new land-uses, which are based on an in-depth analysis of the area’s special features, by taking full advantage of its potentials. What is more, the rehabilitation scheme proposes that the new land-uses and the quarrying activity may co-exist and operate simultaneously for a long period of time. [ABSTRACT FROM AUTHOR]

Most outcrops of good-quality crystalline marble in Mediterranean countries were exploited in Greek and Roman times. Hence, a wide variety of marble is now found in archaeological excavations. The precise determination of the provenance of a marble object is of great archaeological importance, and is now mostly obtained by coupling the petrographic study of a thin section with the analysis of the C and O stable isotopes, or by stereomicroscopy and EPR. The existing databases are considerable but still insufficient, because our knowledge about and study of ancient Mediterranean quarries remain incomplete. The contribution of this research is to add new petrographic and isotopic data on small quarries on the Greek island of Tinos that were exploited in antiquity. This marble belongs to the same geological horizon; it is quite pure, sometimes dolomitic and characterized by a low-T, high-P metamorphism that produced a limited recrystallization (MGS varying from 0.64 to 2.50 mm) on marine limestone protoliths. The petrographic features are quite distinctive: the fabric is strongly lineated and often stressed; and the accessory minerals are ubiquitary quartz, ore minerals, graphite and muscovite. As far as the isotopic data are concerned, δ13CPDB varies from 1.1 to 2.7, and δ18OPDB from −1.7 to −11.4. Both the features and the data have been compared with those of similar marbles used in antiquity, showing that their combination mirrors the fingerprint of the Tinos marble. [ABSTRACT FROM AUTHOR]

This paper is an attempt to contribute to the discussion started in the 1980s and continuing until today, on the origin of orange–brown patinas observed on marble surfaces. SEM and XRD were used in the study of the orange–brown patina growing at the east stoa of Propylaea, at the Acropolis of Athens. The patina consists of an extremely compact, homogenous, 500-μm-thick layer, mainly of hydroxyapatite. The outer part (50 μm) of the layer presents an orange colour attributed to iron in clay particles, which were deposited on the surface of the patina and have gradually been diffused in the bulk. The interface between the phosphatic layer and the marble is very uneven and full of cavities colonised by microorganisms. The phosphatic layer penetrates into the grain boundaries and fills the empty space between the grains. The presence of biological attack at the interface causes progressive erosion and detachment of both the patina and the marble. The minimum presence of oxalates, the absence of microorganisms or remnants of them in the phosphatic layer, the homogeneity and compactness of the patina, give evidence against the theory of biogenic origin. It is suggested that the layer originates from an artificial coating deliberately applied onto the marble surface for protective or aesthetic reasons, when the marble had already been weathered. Possible manmade pastes are suggested. [Copyright &y& Elsevier]

The article provides information on the inscription that was discovered during the excavations conducted in the Athenian Agora in Greece. A fragment of micaceous Pentelic marble was found in January 1981 during the removal of a modern pier north of the north side of the Market Square. According to the author, this fragment of the early fourth century B.C. deals with the relations between Thasos and Athens. Based on the fragment, the author assumes that someone has made a report to the Athenians regarding the properties that have been confiscated and sold in Thasos.

The article examines several unpublished fragments of Greek inscriptions found in the excavations of the Athenian Agora in Greece between 1931 and 1967. These fragments are unrelated to each other and they cannot be attributed definitely to any published documents. The character of the letters in the fragment of white marble suggests a date in the third quarter of the 5th century BC. A fragment of creamy white marble found in the southeast of the Tholos is inscribed in Ionic script. The fragment of bluish white, Pentelic marble appears to be a list of sacred treasures.

This article gathers several small fragments of inscriptions that were found between 1931 and 1967 in the excavations of the Athenian Agora in Greece. A fragment of badly abraded, micaceous Pentelic marble, was found on the North Slope of the Akropolis. Two more small fragments are identified by letter forms, spacing, and marble type as perhaps deriving from a proxeny decree. A small fragment from the upper right corner of a pedimental stele of Pentelic marble in a Late Roman context was also located in February 1968.

The article offers information on the three heads of Sarapis from Corinth, Greece. It is mentioned that during the 1982 excavation season in the east of the Theater of ancient Corinth, a small, bearded marble head which was identified as Sarapis was found. Moreover, two heads of this deity were discovered during earlier excavations at the north of the Basilica on the Lechaion Road and another one in the South Stoa. It is forwarded that the representations of Sarapis varied as the cult progressed and grew in importance.

The article offers information on the Isis Pelagia and a Roman marble matrix from the Athenian Agora. It is posed that this marble fragment offers idea into the worship of Isis in Athens, expounds aspects of the goddess' nautical cult, and forwards the knowledge of the use of stone in the Roman metalworking industry. It is described that the marble of the fragment is dark blue with yellow striations, of poor quality and unknown origin. Moreover, the stone was cut into thin slab with the left edge slightly rough and the lower edge smooth.

The article offers information on a Pentelic marble which was found in the southeast corner of the Agora, Athens, Greece Excavations with inscriptions that deal with the old and new phratry regulations. According to M. Walbank, editor of the Athenian Agora, the said stone was found under the third step which leads to the gate of Athena at the Agora grid square V 13. Through the letter forms rendered on the stone, it can be deduced that the inscriptions can be dated way back to the first half of the 3rd century B.C.

The author discusses the fourth and fifth fragments of ancient stelai excavated in the Athenian Agora. The fragments bear information on leases of sacred properties in Attica. The two stelai or ancient stone slabs contain data indicating that both belongs to the same group of the previously discovered Stelai 2 and Stelai 3. The author noted that Stelai 4 and 5 differs from each other and from the previous Stelai 2 and 3 in terms of marble used. Restoration of the Stelai 4 and 5 are discussed, followed by interpretation on the translation of the text. In Stele 4, the author noted Phaleron as the place of properties' owner. The Stele 5 preserved little information on the renter, guarantor and owner, although it indicated a series of lease of sacred properties.

The article discusses the Greek inscriptions found in the fragments of the Athenian Agora in Greece. The fragments of the Athenian Agora are subject for thorough restorations to augment the previous observations made on its inscriptions. Descriptions of several unedited fragments and texts are discussed, followed by an observation on the possible date of its incision. Catalogue of preserved texts accounts several names of the Diodoros bloodline that were recorded on the fourth century B.C. Archaeologists noted the two fragments from a votive base of Pentelic marble, bearing separately a portion of the preamble of the council of Areopagus and names of ancient tribes. Several inscriptions are preserved but cannot be securely restored.

This article is based on conversations with several participants at the recent Athens conference on the issue of the Parthenon marbles. I hope to bring together threads of discussion so far and hope to do so in a way that is useful and acceptable to both sides of the dispute. [ABSTRACT FROM AUTHOR]

Rockfall consists one of the most harmful geological phenomena for the man-made environment. In order to evaluate the rockfall hazard, a variety of engineering geological studies should be realized, starting from conducting a detailed field survey and ending with simulating the trajectory of likely to fail blocks in order to evaluate the kinetic energy and the runout distance. The last decade, new technologies, i.e., remotely piloted aircraft systems (RPAS) and light detection and ranging (LiDAR) are frequently used in order to obtain and analyze the characteristics of the rock mass based on a semi-automatic or manual approach. Aiming to evaluate the rockfall hazard in the area of Nestos, Greece, we applied both traditional and structure from motion (SfM)-oriented approaches and compared the results. As an outcome, it was shown that the semi-automated approaches can accurately detect the discontinuities and define their orientation, and thus can be used in inaccessible areas. Considering the rockfall risk, it was shown that the railway line in the study area is threaten by a rockfall and consequently the construction of a rockfall netting mesh or a rock shed is recommended. [ABSTRACT FROM AUTHOR]

The article provides information on a debate concerning the conservation of the Parthenon sculptures in Athens, Greece. It mentions the scarceness of marble sculpture preservation and cites the glorious past of the ancient temple of Parthenon and its marble sculptures and decorations. Inasmuch, there are several conservators have tried to preserve those legendary remains of the past.

The article focuses on the joining of the Agora I 4990, a small fragment of gray marble found in Athens, Greece on July 1, 1937 with the right side of IG II2 402. The IG II2 402 is a stone first published by A. Wilhelm and was stored in the epigraphical collection of the National Museum. It is stated that the Agora fragment preserves the right side and is 0.075 meter high, 0.102 meter wide and 0.043 thick. The fragment provides the final letters in lines three to six. The new text of the combined fragments is presented.

Located in the southern Aegean Sea in Greece, the island of Santorini (Thera), lies at the center of the active Hellenic Volcanic arc, between the Cycladic massif in the north and the accretionary wedge of the External Hellenides in the south. The greater part of the island is covered by Quaternary volcanic products, while the pre-volcanic basement is only exposed in two separate localities: (i) around the port of Athinios in the western part of the island schists and metaconglomerates with marble lenses are found, indicating blueschist facies metamorphism, equivalent to the Lower Cycladic Blueschist Unit exposed on other Cycladic islands, and (ii) in the southeastern part of Santorini the mountains Profitis Ilias and Mesa Vouno are composed oflow-grade white Upper Triassic marbles with preserved megalodon shells conformably overlain by yellow dolomites,followed by blueish marbles with chert layers and covered by a wildflysch-typemetasediment. The whole sequence is correlated with the Sub-Pelagonian Unit and is deformed into a complex large refolded synform with the wildflysch-type metasediment in the core. The different tectonic units are separated by the top-to-the SE Santorini Detachment.Unlike on other Cycladic islands, where only cataclastic remnants of the hanging wall are exposed above the detachments, the hanging wall on Santorini is preserved over a thickness of almost 600m and records a complex succession of shallow SE dipping ductile shear zones and localized brittle faults recording a clear top-to-the SE kinematics. Between several meter thick ultra-mylonitic calcite marble shear zones, several tens of meters thick blocks of almost undeformed marbles are preserved. These record large megalodon shells, palaeo-karst, palaeosol and palaeo speleothems. The sub-horizontal to gently SE dipping brittle faults zones are associated with several meter thick cataclastic to ultra-cataclastic fault rocks. The principal slip surfaces are associated with truncated grains, injection dykes and polished surfaces that probably suggest seismic activity during top-to-the SE displacement.Our new structural and microstructural observations give insight into the complex and continuous localization of deformation from ductile to brittle during Miocene displacement along the Santorini Detachment. [ABSTRACT FROM AUTHOR]

The occurrence of glaucophane-bearing marbles on Syros is noteworthy because reports of marbles that contain glaucophane are rare among descriptions of high-pressure marbles. On Syros, the marbles are composed primarily of calcite with or without dolomite and quartz. Much of the calcite in these marbles shows oriented columnar structures that are interpreted as pseudomorphs of prismatic aragonite. The columnar structure is particularly well developed in layers of pure CaCO3 and is one indicator of the high-pressure history of these marbles. Metamorphosed admixtures of carbonate and mafic silicate material yielded minerals that are typical for eclogite facies and blueschist facies. These impure marbles are widespread and contain assemblages of various combinations of glaucophane/ferroglaucophane, Na-pyroxene (omphacite to jadeite), epidote, garnet, paragonite and phengitic white mica. Based on calculated mineral equilibria, the assemblages and mineral compositions in the marbles and associated rocks place narrow constraints on the metamorphic P–T path and the grain-boundary fluid composition of the marbles. The occurrence of glaucophane + CaCO3 + dolomite + quartz suggests that the P–T trajectory that was followed by the rocks crossed a reaction such as albite/Na-pyroxene +dolomite + quartz → glaucophane + CaCO3, but did not exceed the P–T stability of the reaction dolomite + quartz → tremolite + CaCO3. The P–T locations of these reactions are sensitive to fluid composition and indicate that the attending fluid phase was water-rich with XCO2 constrained to be XCO2 of 0·01 best fits the observed assemblages. Relict lawsonite + Al-rich epidote in schists associated with the glaucophane marbles also has a T–XCO2 stability that is limited to fluids with XCO2 2O over most of its metamorphic history. The P–T–XCO2 stability of assemblages common in the schist and marble constrains the P and T maxima for these rocks to about 500°C and 15–16 kbar. These P–T constraints, together with the tectonic fabric of the marbles, suggest that deformation and recrystallization occurred at or near the thermal maximum of metamorphism. [ABSTRACT FROM AUTHOR]