ERE5.1

The initiative of designating the natural stones as Global Heritage Stones Resource by the IUGS is a novel one. The stakeholders are all those countries which record the stone built monuments of cultural significance. The stones used in the monuments with unique geological and architectural attributes and which have been used in the historical past with surviving and/or extinct quarries are being considered for designation of GHSRs. The European nations have been quick in identifying such stones and have proposed many significant stones for designation of GHSR in stark contrast to African, Asian and South American nations which are underrepresented on the world map in terms of designation of GHSR. The need of the hour is to promote the idea to all the nations to come up with the documentation of the stones used in the monuments, the state of preservation of historical quarries, the record and strategy for the upkeep of monuments and the historical quarries. The Project ‘The HERITAGE STONES RECOGNITION: A STEP FORWARD (HerSTONES)’ has been recently granted by IGCP-UNESCO to promote heritage Stones from emerging countries.

How to cite: Kaur, G. and Cardenes, V.: Global Heritage Stones Resource: An IUGS designation, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-12485, https://doi.org/10.5194/egusphere-egu21-12485, 2021.

Granite is the most important building stone in the north of Portugal. The importance of the stones in this region is evidenced by the pre-Roman roots Mor (r), Mur (r) and Mour of place names such as Montemuro, Moreiras, Mouçós, and Mourelhe. These roots indicate the existence of building stones used since ancient times in these places.

The quarries of the main building stones of historical buildings were generally in the vicinity of the buildings. Formerly, stonemasons carved mason's marks on ashlars. The mason's marks are lapidary signs to indicate the work carried out by each one. The mason's marks are generally symbolised by the initial of the stonemason's name. They are often found on dressed stones in buildings and in other public structures.

Nossa Senhora de Guadalupe church of Mouçós (possibly 16^th century) has typical characteristics from the late Romanesque. It is located in Vila Real (North of Portugal). It is made up of three volumes: a single nave, a lower rectangular apse, and a sacristy attached to the apse. The exterior of this church is preserved almost unaltered in its original state. Each of the granite ashlars that make up this church has a mason's mark in the center of its face.

The mason's marks of the church have been identified; all the ashlars with visible mason's marks have been mapped, and a glyptographic study has been carried out. This has made it possible to calculate the number of stonemasons that worked in the construction of the church and the number of ashlars that were transported in each carriage, and to determine the construction phases of the church.

Eight cubic samples have been cut to calculate the granite’s hydric properties (effective porosity, water absorption and bulk density) according to UNE-EN:1936. Ultrasound wave velocity was measured according to UNE-EN:14579. Furthermore, three thin sections have been made to characterise the granite petrographically under a polarisation microscope Leica DM-4500-P. A mosaic of photomicrographs has been made to evaluate the petrographic properties.

There are six main types of mason's marks in Nossa Senhora de Guadalupe Church. All quarrymen extracted the stones from the same quarry, or from nearby quarries. The mean effective porosity of the building granite is 3.2%±0.3, and the mean water absorption is 1.2%±0.1. Its mean bulk density is 2566 kg/m³±61.0 and its ultrasound P wave velocity is 2920 m/s±98.3.

The mason's marks are preserved because of the excellent petrographic and petrophysical properties of Mouçós granite. Further, Nossa Senhora de Guadalupe church was protected with lime plaster during the past centuries, and the plaster was not removed with the projection of abrasive particles.

The use of analytical techniques such as petrography, ultrasonic P wave velocity and the determination of hydric properties will guarantee the quality and durability of a sustainable restoration.

The historical quarries, forms of traditional stone extraction and uses of Mouçós granite constitute a heritage that must be safeguarded.

Acknowledgements: The Fundação para a Ciência e a Tecnologia (FCT) of Portugal. CEECIND/03568/2017.

How to cite: Freire-Lista, D., Campos, B., and Moreira da Costa, P.: The Heritage Stone of Nossa Senhora de Guadalupe Church, Mouçós, North of Portugal: Characterisation and Glyptography, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-4536, https://doi.org/10.5194/egusphere-egu21-4536, 2021.

Since the establishment of the Heritage Stone Subcommission by the International Union of Geological Sciences (IUGS), in 2011, idealized with the purpose of designating stones of historical significance to compose the Global Heritage Stone Resource (GHSR), 22 of them have been designated. The nationalities of these GHSR are: 3 British, 1 Norwegian, 2 Belgian, 2 Swedish, 1 Slovenian, 3 Italian, 2 Portuguese, 3 Spanish, 1 Maltese, 1 Indian, 2 American and 1 Argentine. So far, no Brazilian stone has been designated as GHSR. We can observe in monuments and buildings in the Brazilian territory the following imported GHSR: Lioz Stone and Estremoz Marble from Portugal, Carrara Marble and Rosa Beta Granite from Italy and Larvikite from Norway. The use of stones from Portugal and Italy is related firstly to the Portuguese colonization and, later, to economic cycles, such as rubber and coffee, with Italian immigration being significant to the coffee cycle. The presence of Lioz is major, however, it is found almost exclusively in some Brazilian coastal capitals, such as Rio de Janeiro, Salvador and Belém. The churches of Salvador are richly decorated with numerous varieties of Lioz. In Belém, it is found in the Basilica of Nossa Senhora de Nazaré, among other churches, and in many tombstones in the Nossa Senhora da Soledade Cemetery. Estremoz Marble is found in commercial buildings and tombstones. In the city of São Paulo, lots of buildings have internal cladding and ornaments made in Carrara Marble, e.g. Municipal Theater, Palace of Justice, Metropolitan Cathedral and Obelisk Mausoleum for the Heroes of 32. In the city of Rio de Janeiro, the tomb of Orville Derby (founder of the Geological Survey of Brazil) at São João Batista Cemetery, among others, is decorated with Carrara Marble, which can also be seen in tomb art of Salvador, Belo Horizonte, Curitiba and São Paulo. Rosa Beta Granite can be seen at Monument to Bartolomeu de Gusmão in the city of Santos, costal area of São Paulo State. The use of Larvikite is contemporary. This stone is mainly present in tombstones, for example, at the Consolação Cemetery in São Paulo, but it also decorates the façades of several commercial buildings, both in capitals and several Brazilian cities. In Brazil, several types of Brazilian stones are found in monuments and religious or administrative buildings. These stones, which have been used since Colonial Brazil, are characteristic of certain regions, such as Augen Gneiss in Rio de Janeiro, Itaquera Granite in São Paulo, beachrock in northeastern Brazil, quartzites and steatite in Minas Gerais, among others. Some of them constitute UNESCO World Heritage Sites, and due to their historical importance to our heritage, these stones may be indicated as GHSR in the future.

How to cite: Del Lama, E. A. and Costa, A. G.: Global Heritage Stone Resource in Brazil, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-8531, https://doi.org/10.5194/egusphere-egu21-8531, 2021.

The diagnosis of the conservation state of monumental structures from constraints to the spatial distribution of their physical properties on shallow and inner materials represents one of the key objectives in the application of non-invasive techniques. In situ, CRP and 3D ultrasonic tomography can provide an effective coverage of stone materials in space and time. The intrinsic characteristics of the materials that make up a monumental structure and affect the two properties (i.e., reflectivity, longitudinal velocity) through the above methods substantially differ. Consequently, the content of their information is mainly complementary rather than redundant.

In this study we present the integrated application of different non-destructive techniques i.e., Close Range Photogrammetry (CRP), and low frequency (24 KHz) ultrasonic tomography complemented by petrographycal analysis based essentially on Optical Microscopy (OM). This integrated methodology has been applied to a Carrara marble column of the Basilica of San Saturnino, in Byzantine-Proto-Romanesque style, which is part of the Paleo Christian complex of the V-VI century. This complex also includes the adjacent Christian necropolis in the square of San Cosimo in the city of Cagliari, Sardinia, Italy. The column under study is made of bare material dating back probably to the first century A.D., it was subjected to various traumas due to disassembly and transport to the site, including damage caused by the close blast of a WWII fragmentation bomb.

High resolution 3D modelling of the studied artifact was computed starting from the integration of proximal sensing techniques such as CRP based on Structure from Motion (SfM), with which information about the geometrical anomalies and reflectivity of the investigated marble column surface was obtained. On the other hand, the inner parts of the studied body were successfully inspected in a non-invasive way by computing the velocity pattern of the ultrasonic signal through the investigated materials using 3D ultrasonic tomography. This technique gives information on the elastic properties of the material related with mechanical properties and a number of factors, such as presence of fractures, voids, and flaws. Extracting information on such factors from the elastic wave velocity using 3D tomography provides a non-invasive approach to analyse the property changes of the inner material of the ancient column. The integrated application of in situ CRP and ultrasonic techniques provides a full 3D high resolution model of the investigated artifact. This model enhanced by the knowledge of the petrographic characteristics of the materials, improves the diagnostic process and affords reliable information on the state of conservation of the materials used in the construction processes of the studied monumental structure. The integrated use of the non-destructive techniques described above also provides suitable data for a possible restoration and future preservation.

Acknowledgments: This work was partially supported by FIR (Fondi integrativi per la Ricerca) funded by the University of Cagliari (Italy). The authors would also like to thank the Ministero dei Beni e delle Attività Culturali. Polo Museale della Sardegna and Arch. Alessandro Sitzia for their kind permission to work on the San Saturnino Basilica.

How to cite: Casula, G., Fais, S., Cuccuru, F., Bianchi, M. G., Ligas, P., and Sitzia, A.: Decay detection in an ancient column with combined close-range photogrammetry (CRP) and ultrasonic tomography., EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-2022, https://doi.org/10.5194/egusphere-egu21-2022, 2021.

Rajnagar Marble, occurring around Rajnagar and Kankroli towns in Rajsamand district of south-central Rajasthan make up the largest marble deposits in India. Rajnagar Marble belongs to late Paleoproterozoic Aravalli Supergroup.  It is mostly white, coarse-grained and compact dolomitic marble. Mining is currently being carried out at several, small to medium-sized, open quarries using both conventional and mechanized operations. Although the Rajnagar Marble has been extensively used in archaeological monuments for centuries, it received recognition since the construction of spectacularly carved embankment (Nau-Chowky) of the Lake Rajsamand built during the period 1662-1676 CE. Its use has been recorded in the 8^th century Eklingji Temple and numerous other temples in Udaipur and vicinity. Besides temples, embankments, step-well constructions, Rajnagar Marble was preferred for carving of idols of various Hindu deities, including the famous 12^th century Palasma 7-horse drawn chariot Sun idol with nine planets revolving around it. But use of this Dev-Patthar (God's Stone), was avoided for flooring and private dwellings of humans in keeping with the Hindu mythological beliefs. Hence for the residential buildings, Rajnagar Marble was popularly used as a unique ground-in-hand-mill-and-sieved-through-muslin-sieve marble powder-lime paste (~100-micron size) to give the walls, pillars, lanterns, or even floors the "marble-finish". An intangible heritage process typical and unique of the erstwhile Rajputana.  Most palaces and havelies of Mewar area, including the five palaces of Udaipur namely, the City Palace Complex, Jagniwas (now the Taj Lake Palace Hotel), Jag Mandir, Lakshmi Vilas Palace and the Sajjangarh (Monsoon Palace) were all built partly in Rajnagar Marble stone, but mostly with marble powder-lime paste finish on lime-sand-quartzite masonry works.  Numerous architectural sites such as Moti Mahal, embankments of Fateh Sagar Lake and Rajsamand Lake, Eklingji Temple, Jagdish Temple, Saheliyon-ki-Badi, cenotaphs of the Royal family members at Ayad (1620 CE onwards) were built of Rajnagar Marble.

The low water absorption, high bulk density and high compressive, shearing and tensile strength of the Rajnagar Marble, and its ‘blockability’ made it technically suitable for monuments that have sustained for five centuries or more, with no signs of weathering and discoloration. The Rajnagar Marble entered the global market in the later 20^th century with its export to various countries including the Middle East and Japan. At present, it is extensively used in building and handicraft industry and is also famous for contemporary artworks. In light of these variety of applications of the Rajnagar Marble, we propose ‘Rajnagar Marble’ for the designation of ‘Global Heritage Stone Resource’.

How to cite: Garg, S., Agarwal, P., Ranawat, P., Kaur, P., Singh, A., Saini, J., Acharya, K., Pandit, M., and Kaur, G.: Rajnagar Marble: a prominent heritage stone from Rajasthan, India, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9394, https://doi.org/10.5194/egusphere-egu21-9394, 2021.

Restoration mortars are a designated group of products made to repair damaged masonry. They must be compatible with the former support of stones and bricks, and protect original materials from environmental agents; aesthetical and historic aspects must not be neglected. 

To improve the ecological footprint of the restoration mortars while keeping their efficiency, we have tested several combinations of lime with aggregates and additives. Recycled and natural materials were used as additives such as pinecone resin, semi-milled cones of pine, milled glass waste, brick production residue.

For research purposes different physical properties have been measured in prepared mortars: porosity, density, capillarity absorption, moisture absorption, water vapour permeability. We have also tested the mechanical properties and the P and S waves velocities (from which dynamic Young's modulus and Poisson’s ratio were inferred). The durability of mortars has been estimated by salt crystallization and frost/thaw cycles.

The life cycle analysis (LCA) of such mortars allows us to understand the carbon footprint of each manufacturing process. Considering this we selected the raw materials, from an environmental and commercial point of view, to produce mortars fulfilling sustainability requirements. As a result, the developed mortars are compatible with aged stones, minimize environmental impact, and use minimum natural resources.

 Twenty mortar formulations with three different types of limes (NHL5, NHL3.5, CL90) and two different aggregates (siliceous and calcareous) have been studied using the LCA. Currently, five new formulations are being selected to be tested on Euville limestone. Adhesive strength (James Bond test), and physical properties will be measured on these mortars. 

How to cite: Diaz-Basteris, J.: New sustainable mortars for stone restoration in the context of climate change, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9638, https://doi.org/10.5194/egusphere-egu21-9638, 2021.

How to cite: Wyse Jackson, P., Caulfield, L., Forde, A., Conlon, I., Cox, P., and Sevastopulo, G.: Valentia Slate, Co. Kerry, Ireland: a Global Heritage Stone Resource proposal, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-13576, https://doi.org/10.5194/egusphere-egu21-13576, 2021.