Heritage, Volume 2, Issue 4 (December 2019) – 10 articles

The knowledge that archaeological prospection is shaped by modern attitudes and procedures is important to the future of archaeology. Although geophysical studies have been applied to archaeological and historical sites over time with intermittent success, it is possible to derive great effects when used appropriately. It is most significant when applied in a well-integrated research design where interpretations are established and explored. The representation of survey data involves the knowledge of both archaeological evidence and the way it is stated in geophysical terms. Proper instrumentation, study design, and information processing are important for success, and these must be adapted according to the specific geology and archaeological evidence of each survey location. In this context, the regulation of information quality and spatial quality are important. This Special Issue of the Heritage journal expects to accumulate unique research articles on geophysical surveys for archaeology and cultural heritage preservation. Full article

Remote sensing techniques, such as LiDAR and photogrammetry, are used by researchers exploring the spatial distribution of weathering features in historic masonry. These well-established tools provide users with a perspective of the processes affecting the surface of masonry blocks; however, they cannot provide information on the alteration occurring subsurface. Geophysical tools are being explored as a potential approach to observe the variation in material properties beneath masonry block surfaces and to examine the patterns of deterioration across wall sections. Applying such techniques inform the development of conceptual models of weathering at the block to building wall scale. In this study, ground-penetrating radar (GPR) was selected to inspect the subsurface condition of the wall section of an historic church wall, where areas of granular disintegration and flaking can be observed. 3DGPR was selected for this task, as its use of regular grids during data collection make it better suited for detecting features within an area. Three high-frequency antennas, 1.2 Ghz, 1.6 Ghz and 2.3 Ghz, were run across the study area in a series of 80 cm by 80 cm grids. The data were collated within GIS, where observed features were annotated onto a schematic of the wall surface. The 3DGPR outputs identified anomalies within this structure that could not have been as easily interpreted using a 2DGPR transect. However, as 3DGPR relies upon interpolative techniques to estimate the returns between observation transects, the validity of features detected in these locations need to be tested. The results of this application of 3DGPR identified variable weathering response across the wall section, relative to elevation. These observations were used to develop a conceptual model linking these findings to seasonal variation in the capillary rise of groundwater, upward from the base of the church wall. Through these findings it is possible to see how GPR can assist in developing our understanding of the processes threatening heritage buildings. Full article

Aluminum alloys are very interesting witnesses of industrial and technical development. The first ever developed was Duralumin, a light metal with good mechanical properties. In the 1930s, the rise of nationalism stimulated research and development, generating various aluminum alloys. This work reports the comparison of two versions of aluminum alloys, which were found in collected parts of WWII crashed aircraft from four nations: a Messerschmitt Bf 109 (DE), a Dewoitine D.520 (FR), and a P-51 Mustang (USA) and an Avro Lancaster (United Kingdom). The first version of alloy with magnesium content below or equal to 1 wt.% and the second version with higher magnesium content (1.5 wt.%), were identified as respectively AlCuMg1, AlCuMg2 in Germany; Duralumin, Duralumin F.R. in France; Hiduminium DU Brand, Hiduminium 72 in the UK and 17S, 24S in the USA. This study uses a multiscale approach based on historical research complimented by laboratory analyses of materials directly collected on the crashed aircraft. It allows a comparison and a better knowledge of the alloys used in each nations: their chemical composition, designations, microstructure, and mechanical properties are investigated. Full article

We propose a new method for dating ancient linen threads by inspecting their structural degradation by means of wide-angle X-ray scattering. X-ray dating of a textile sample can be performed nondestructively and on a submillimeter area, e.g., 0.2 × 0.5 mm², exploiting new table-top X-ray micro-sources. A theoretical formula is derived for dating linen samples directly from wide-angle X-ray scattering measurements. Our preliminary results show that X-ray dating results are in agreement with other dating sources, such as the radiocarbon method and historical records, if some conditions are satisfied. Indeed, this new dating method can be applied only to threads not older than about thirty centuries because of the saturation of the structural degradation with age. Moreover, the method can be applied only on textiles in which cellulose degradation is mainly due by natural aging arising from thermal, hydrolytic, photolytic, photochemical, and oxidative processes. Analyses can be repeated several times on the same sample, which remains unaltered for other complementary characterization procedures. The proposed X-ray dating of some ancient linen fabrics opens the way to explore limits and potentialities of this new approach and to further develop a new dating method, alternative to the existing ones for specific applications in archeological studies. Full article

Scrub vegetation encroaches into the proximity of many monuments at Myanmar’s Bagan Cultural Heritage Site, as can be seen at many other monuments on the world. The extensiveness of scrub vegetation can interfere with the integrity of the cultural landscape when ignored by site management. The current study examined how significant the occurrence of scrub vegetation might be, quantifying the canopy coverage with relative occupancy of other components in the sacred compounds. The sacred compounds in Bagan enclose religious monuments in environments classified as farmland, monastic residences, accessways, shrub-hosting areas, and scrub vegetation. The coverage of scrub vegetation was more than a quarter of the area of sacred compounds, whereas that of shrub-hosting patches was about half. The other components occupied less than one-fifth of the area. The associated occurrence of scrub vegetation indicated the invasion of alien species from the drier hinterland to the riverside of Ayeyarwady. While such a situation reveals site management as a priority, the presence of cultivated farmland in the vicinity of monuments represented suppression of weedy growth that may later facilitate the occurrence of scrub-type plants. This study suggests cultivation as a reasonable practice for the integrity of the cultural landscape and safeguarding the monuments in Bagan. Full article

The painting collection of Santa Casa da Misericórdia da Lourinhã is amongst Portugal’s most notable and scarcely best-known cultural heritage. The artistic interest of this pictorial group, besides the advanced state of degradation of a number of the paintings, together with the ruined circumstances of the building accommodating the collection, today in reconstruction, were the key reasons for this study. Thermo-hygrometric measurements were carried out. A multianalytical methodology incorporating micro-X-ray diffraction (µ-XRD), energy-dispersive X-ray fluorescence spectroscopy (EDXRF), scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS), micro-Raman spectroscopy (µ-Raman), micro-Fourier transform infrared spectroscopy (µ-FTIR) has been followed for the study. These analyses were complemented by infrared photography (IRP) and reflectography (IRR), allowing the study of the underdrawing technique. The results of this study were compared with previous ones of the painter’s workshop and important distinctions and similarities were found within the materials and techniques used. This analysis methodology on materials contributes to safeguarding and the ensuing community awareness of this cultural heritage in danger. Full article

Currently the application of consolidants based on nanoparticles is common practice among restorers. Consolidants should not modify the properties of original materials according to international recommendation, which requires previous studies to decide the optimal option. The selection must be based on empirical results, and not only in the expertise of the restorer, because the consolidant’s effectiveness is influenced by its own properties and other factors such as the characteristics of the artwork (elemental composition, porosity, texture, etc.) and its context (temperature, relative humidity, etc.). Moreover, new protocols must be sustainable and compatible with on-site restoration. A new protocol to test consolidant nanoparticles has been designed and assessed. This is based on easy trials and low-cost techniques—digital microscope, colorimeter, peeling test and ultrasound—that could be employed by restorers in situ. In this paper, different consolidant nanoparticles were tested on stones from two historical quarries. The first treatment was SiO₂ nanoparticles, and the second, a new nanocomposite of Ca(OH)₂ and ZnO quantum dots that allows us to measure penetration depth easily and discern the treated areas under UV lights. This second treatment was the best option for the studied stones, validating the protocol designed for the choice of consolidants. Full article

The massive bombings during World War II (WWII) have had a lasting impact across the Italian landscape. The problem of dangerous unexploded bombs is particularly relevant since the bombsites are buried beneath the soil close to inhabited and/or touristic areas. Archaeological sites, such as Pompeii and Vulci, were heavily bombed, and nowadays, archaeologists excavate these bombs during their digs. Thus, there is a real risk to people’s safety. While the aerial photo collection is a powerful record of the landscapes of wartime Italy, plotting buried unexploded bomb hazard maps remains important in identifying their precise location in the modern landscape. Ground penetrating radar (GPR)—a non-destructive technique (NDT)—can help detect these bombs buried beneath the soil by providing an accurate horizontal and vertical position. Using aerial photos and NDTs, such as GPR, this future project explores the WWII human experience to preserve and manage the safety of both the archaeological heritage and involved users by using the data to create an open-access WebGIS platform. Full article

Old manuscripts are among the most important elements of the cultural and historical heritage of ancient knowledge. Unfortunately, many of them suffer from degradation, mostly those written with iron gall inks. In the present work, a study using non-destructive techniques was designed with the aim of analyzing the elemental composition and structural characteristics of iron gall inks, reproduced in laboratory, paper and their interaction when the ink is deposited on paper, inducing the paper degradation. Proton induced X-ray emission, X-ray diffraction and Fourier-transform infrared spectroscopy provided the elemental and structural information, and photography under infrared (IR) and ultraviolet (UV) light allowed the differentiation between manufactured inks. Results show that the first step of inked paper deterioration is due to acid-hydrolysis of the cellulose and the presence of reactive Fe(II) species by reducing the crystallinity index of the paper, which is affected depending on the ink recipe and the starting raw materials. These results will be useful to future studies on ancient documents written with iron gall inks, which suffer deterioration due to ink corrosion, and to differentiate between the different paper degradation mechanisms. Full article

The International Council on Monuments and Sites (ICOMOS) Florence Charter 1981 on Historic Gardens sets the first guidelines for the definition of a historic garden, in which sites such as large parks, whether formal or landscape, are included. Since then, there is a continuous effort worldwide on issues of historic garden acknowledgement, conservation, restoration and management. Countries with garden and park tradition, such as the U.K., USA, France and others, have several sites registered and protected. Furthermore, historic garden and park associations exist in Italy, Spain and Portugal, among other nations. In Greece, there is no specific official policy or association regarding historic parks, gardens or landscapes. Greek law includes historic gardens and parks within the spectrum of works of art, places of outstanding natural beauty and historic places/lands for partial or absolute protection, and, thus, attempts in identifying historic landscapes fall generally in other categories, but law specified for historic gardens. However, in both the Greek ratification of the European Landscape Convention and the European Biodiversity directives, there are aspects one could interpret as very useful for the acknowledgement and policy-making on historic gardens and parks. In this paper, an overview on historic gardens and parks abroad and in Greece is attempted, along with aspects of acknowledgement, protection, conservation, restoration and management. Finally, a first attempt on methodological outlines for the acknowledgement and conservation of historic gardens and parks in Greece is presented. Full article