Platy limestone
as cultural heritage

The project Limestone as the common denominator of natural and cultural heritage along the karstified part of the Adriatic coast covers various regions of the eastern coast of the Adriatic Sea: the Italian and Slovenian parts of the Kras/Carso region, the Istrian peninsula, the Zadar area of northern Dalmatia, Herzegovina, and the central part of Dalmatia between Split and the Pelješac peninsula.

The area of research was limited according to the geographically-fixed working field of each partner where, with the exception of the small area of Dolina, platy limestone represents the singular traditional building material. With this limestone modest but beautiful living spaces were created. One of the key features of the coastal landscape are buildings made entirely of stone, with slate roofs, and representing an important part of the region's cultural heritage. Different aspects of Platy limestone as cultural heritage were addressed through the various research assignments included in Work Package 4, from historic use through modern conservation and the reuse of platy limestone objects.

The general focus of the work under 4.1 – Historic use of (platy) limestone in the Adriatic karstic areawas to point out the historical value of the stone architectural objects, where platy limestone was used to fashion cover plates for roofs as an important, integral part of the building. Limestone was also widely used for several structural features and details, including eaves, gutters, pavements, cistern scarps, chimneys, benches, tables, etc. (see Supplement 3.I).

The research had to focus on commonalities and regional specificities related to the excavation, elaboration and use of the stone

In order to realize this work an outline of the historic presence of platy limestone had to be prepared and the role of platy limestone in the Adriatic region outlined, based on historic sources and on existing scientific literature. The research had to focus on commonalities and regional specificities related to the excavation, elaboration and use of the stone, to determine how the stone was used in the past and how it is used in the framework of present architectural heritage. An inventory of the existing vernacular and representative stone architecture with stone roofs made of platy limestone was carried out as an important component of this part of the work. Certain case studies were selected that will be taken as representative for future approaches to the traditional architectures of the region (Supplement 3.I).

The second important component within the context of these selected architectural objects was to determine, with the help of geological analyses, the origin and quality of the stone building material, which forms the backbone of the basic knowledge to be applied in the future maintenance of these historical buildings.

To this end we focused our work on activity 4.2 – Limestone quarries as cultural landscape heritage, where our investigations centred on the centuries-long historic presence of limestone quarries in the Adriatic regions as cultural landscape, with regard to chronology of their use (and abandonment), geographic location, connectedness to urbanized areas and crafts centres, transport routes, interdependence with the socio-economic development of the region and similar (Annex 3.1).

Activity 4.3 – Cross-border issues in conservation and restoration of platy limestone is based specifically on the analyses of selected showcase platy limestone roofs in order to determine the state of conservation of the stone as well as of past interventions. A total of 60 limestone samples were analysed to determine the state of conservation of the stone as well as of past interventions and to identify current trends in conservation and restoration techniques, as well as their positive and negative effects (Annex 3.2).

Legislation related to natural and cultural heritage played an important role in the project, as seen in 4.4 – Shared guidelines for conservation and restoration of platy limestone. It was important to identify instances of good practice in documented cases on a regional scale in the Adriatic region and to focus these experiences on linking regional and local specificities of limestone use in a cultural context and in relation to their regional/local properties. Sustainability in conservation requires acknowledgement of both good and bad practices in past interventions. Issues connected with national, regional and local legislation related to cultural heritage and preservation of cultural landscape were analysed as well as existing official requirements for stone conservation so as to propose specific guidelines for the protection of platy limestone, quarries and use of the stone in cultural heritage, namely in the built environment (Supplement 3.III: Conservation Guidelines for Platy Limestone in Architectural Cultural Heritage).

In order to realize these primary goals one central task was to analyse the connection between historical quarries and historical buildings, to analyse the legal and practical possibilities of reusing existing stone material through certain maintenance processes.

Collecting documentation and evidence related to type, quality and scope of stone buildings with platy limestone roofs constituted a basic project task in selected regions of the eastern Adriatic coast and related hinterland areas.

With 4.5 - Geo-mapping of Adriatic heritage in limestone, fieldwork in the selected areas provided a set of practical cases related to use of the stone, where the representative items were inventoried according to architectural and conservational parameters (origins/locations of the platy limestone used on the building, function, aesthetic values, state of conservation, state of deterioration, past restoration interventions and similar). It is particularly important that the showcase projects with particularly profound elaboration be integrated into the dissemination applications developed in the project.