5 Archaeological material

5

Archaeological material

Object

Murals and mosaic in the north-eastern arm of the cryptoportico in the Els Munts Roman villa

Material/Technique

fresco mural paintings on intonaco made from lime and sand (side walls) and opus tessellatum mosaic (flooring)

Title/Topic

Decorative coatings, painted

Date/Period

Mid-1st century–early 2nd century. Peak of the Roman empire

Dimensions

North-eastern arm of the cryptoportico: 27.50 × 3.50 m

Location

Side walls (murals) and floor (mosaic) of the cryptoportico in the south-eastern section of the Els Munts Roman villa site in Altafulla

This article will describe the conservation-restoration intervention on the preserved coatings on the cryptoportico in the Els Munts Roman villa, as well as the murals on its side walls and the mosaic floor.

The Els Munts Roman villa is from the time of the height of the Roman Empire and displays great architectural and decorative wealth. The cryptoportico is found in the residential part, built on the south side of a hill facing the sea. It is a semi-underground corridor, in the shape of an L opening out towards the west, and provided access to the private rooms of the domus. In situ, the decorative elements are preserved, and they are the object of this restoration. The fresco murals and opus tessellatum flooring are the most significant decorative remains from the Els Munts site.

State of conservation

Overall, before restoration, the cryptoportico presented a poor or very poor state of conservation, which varied depending on the area. The preserved remains were affected by various pathologies, which altered the site in terms of conservation and aesthetics.

The main alterations were down to environmental conditions, proximity to the sea and damp, saline surroundings. Meanwhile, exposure to the outdoors led to a generalised presence of dust, dirt and sediment deposits, as well as animal debris, such as excrement and insect nests. But above all, water was the main cause of alteration to the site, through both direct physical action and rising damp. The fibre cement panels on the roof broke repeatedly over the years, though they have been repaired again during this intervention.

This failure affected the flooring and the tops of the walls, which were eroded by water leaks. The presence of water was accompanied by the formation of hardened, carbonated deposits and the emergence of significant saline efflorescences. There was also some biological growth, which caused various alterations, like the growth of roots of nonseed plants, the production of acids, the formation of oxalates, and chromatic changes.

Intervention

The intervention aimed to improve the site’s state of conservation by stabilising and consolidating the alterations. The other objective was to improve its aesthetic dimension. In this area, special attention was paid to cleaning operations and final presentation systems, which varied depending on the area and the elements, but always with overall consistency and unity in mind.

The intervention processes were carried out alternately or simultaneously, depending on each area’s needs, and with different treatments for different elements and materials, such as the fresco murals and the stone and ceramic mosaic.

Restoration

Arcovaleno Restauro, SL: Rudi Ranesi (coordinator), Davide Belfiore, Sílvia Bottaro, Maria Cardenal, Neus Casal, Lorenzo Masi and Tina Núñez. Neus Casal and Caridad de la Peña (documentation)

Audiovisual report Verònica Moragas

 Close-up of the Solomon’s knot that makes up the geometric design on the flooring mosaic

 General view of the cryptoportico after the conservationrestoration intervention

  Partial view of the mural paintings on the southern wall of the cryptoportico before and after the intervention. We can see the recovery of the painted architecture, which consists of a marbled base and rectangular decorative panels in alternating horizontal and vertical orientation

The operations began with mechanical cleaning to remove any dust and loose deposits. This process also removed part of the acrylic resin from the murals. Next came a chemical cleaning process, with acetone applied through impregnation with a paintbrush and Japanese paper. Moderately hardened deposits were removed using a scalpel, a glass fibre pencil and Wishab® sponges.

Then, a biocide product was applied to reduce the biological attacks, and as many of the plant roots present inside the intonaco mortars were removed as possible. To remove the soluble salts, efflorescences were removed mechanically and the occasional deionised water swab was applied to the areas with carbonated salts.

Any loose mortar was consolidated through the injection of hydraulic mortars. In the case of the paintings, meanwhile, we repaired material losses by bevelling the perimeter, sealing cracks and fissures, and plastering any hollows that altered the visual continuity of the decorated surfaces. Chromatic integrations were carried out with watercolours, through glazes or tratteggio, depending on the case. As for the mosaic, any loose tesserae were secured. To reintegrate any areas with losses, other tesserae were used from the same mosaic, having been preserved at the National Archaeological Museum of Tarragona (MNAT).

The intervention described has led to great results for the cryptoportico site, but it is clear that constant maintenance is required to avoid any more deterioration of the materials that make up the site.

— Neus Casal and Rudi Ranesi

Planimetric study and mapping of a section of the mural paintings on the southern wall

Planimetric study and mapping of a section of the flooring mosaic Alterations

surface alterations  Calcareous concretions  Calcareous concretions

previous interventions  Added mortars

fractures and deformations  Fissures/cracks

separation and detachment  Decohesion. Air pockets  Disintegration of mortars  Disintegration of paint (pulverulence/peeling)

loss of material  Loss (polychrome/mortar) Intervention

removal of added mortars  Removal of mortars (bevelling/filler)

consolidation  Injection of PLM into hollow areas  Adhesion of fragments with PLM

reintegration  Material. Lime mortar  Chromatic. Retouching with watercolour

Alterations

surface alterations  Saline efflorescences  Carbonated deposits  Calcination / blackening

separation and detachment  Disintegrated or worn tesserae  Loose tesserae  Loss/mortars Intervention

cleaning  Removal of deposits and added mortars

consolidation  Ethyl silicate  Lime and sand mortar and loose tesserae

reintegration  Lime and sand mortar and loose tesserae

Material/Technique Opus tessellatum

Title/Topic

Mosaic of Paris and Aphrodite or of Theseus and Ariadne

Date/Period

3rd century CE

Dimensions

3.12 × 2.39 m

Origin

Roman village of Can Pau Birol, Bell-lloc del Pla, Girona (Gironès county)

Location

Archaeology Museum of Catalonia

Coordination

M. Àngels Jorba (CRBMC), Laura Lara (MAC-Girona) and Sílvia Llobet (Àbac Conservació-Restauració, SL)

Restoration

M. Àngels Jorba (CRBMC) and Sílvia Llobet (Àbac Conservació-Restauració, SL); Pol Camps and Nieves Marí (CRBMC interns and collaborators); and Laia Codina, Laura Gómez, Lídia Pérez and Mireia Sabaté (intern students)

Years of restoration

2015-2016

In 1876, the remains of the Roman village of Can Pau Birol were discovered, of which we now know three mosaics: the Mosaic of the Circus, the Mosaic of Bellerophon and the Chimera and the Mosaic of Theseus and Ariadne.

The Mosaic of Theseus and Ariadne is preserved in the Archaeology Museum of Catalonia in Girona. In 2016, the museum organised the temporary exhibition «3 mosaics, 3 museums: 140 years of the Roman mosaics of Bell-lloc (Girona)», which involved a new study of the flooring, as well as the restoration of the mosaic.

This mosaic is preserved in four fragments, because it was extracted, restored and placed on a new reinforced concrete support in 1941. For this reason, we have received little information about its construction technique; only part of the mortar bed for the limestone tiles remains, in twelve different hues.

The decorative motif shows a geometric field that begins on one side, in which we find a border of fractional meanders, followed by an orthogonal design of intersecting circles with an inner flower. The emblem –possibly set in the upper central part of the room –has a white background on which the mythological scene unfolds.

State of conservation

As for its structure, it showed a varied pathology. The most serious alterations were located in the cement backing, as the iron mesh suffered advanced stages of oxidation that generated cracks, fissures and detachments. At the same time, sunken areas were identified due to previous extraction works and the placement of the piece on the new backing.

The gaps were reintegrated with cement, although rows reintegrated with original tiles on a plaster bed were documented among the fragments.

The entire tile surface featured several layers that masked the original colours and design of the mosaic. A first layer of carbonates —not completely removed during the previous

Close-up of the final cleaning work with microblasting

intervention— was identified, as well as several yellowed layers of waxes or resins.

Intervention

The intervention was carried out in two phases. The first one focused on removing the reinforced concrete backing, so it was necessary to apply gauze to the front first in order to keep the tiles in place. Each fragment was then turned around, and the cement was gradually reduced and the metal mesh removed using a grinder or other pneumatic tools.

Once the cement had been removed from the back of the tiles, the new backing was applied using two layers of hydraulic lime mortar and light aggregates. Besides that, a fibreglass mesh was inserted between the two layers. When the mortars had dried, the fragments of the mosaic were turned around again, and the gauze was removed. The tiles were cleaned by chemical and mechanical means, and, lastly, some microblasting took place.

For the final assembly, the various fragments were placed on rigid honeycomb-shaped panels, to give rigidity to the whole piece and allow for it to be displayed in a museum. At the same time, the tiles were grouted and the gaps were filled using a hydraulic lime mortar and selected aggregates, in order to achieve a granularity and tone in harmony with all the decorative motifs.

— Sílvia Llobet

Close-up of the emblem representing Theseus and Ariadne before and after cleaning

Final state of the mosaic displayed in the MAC-Girona museum

Close-up of one of the fragments now placed on the new honeycomb backing

Object

Baths: walls, flooring, various coatings, murals, mosaics and claddings

Material/Technique

Wall structures made from local limestone, similar to the stone from El Mèdol; opus caementicium, opus vittatum, opus incertum and opus quadratum. Coatings: fresco mural paintings, cladding made from marble and Alcover stone, and opus signinum and opus tessellatum mosaics.

Date/Period

Roman period (late 1st century - mid-2nd century until the 4th century)

Dimensions

Walls: 1.256 m²; flooring: 1.860 m²

Location

South-western side of the Els Munts Roman villa, Altafulla (Tarragonès county)

This article will look at the conservation-restoration intervention on the wall coatings and flooring preserved in various areas of the southern baths in the Els Munts Roman villa. Work was done on a total of eleven areas that make up the southern baths, and the intervention is being viewed as part of the full restoration of all of the baths, planned for future phases.

The southern baths are located at the far south-west of the Els Munts Roman villa site. This is one of the most significant bath complexes surviving from the height of the Roman Empire. The main access to the building was from the porticoed ambulacrum, which joined the lower baths to the domus and was surrounded by the villa’s residential area.

The spaces retain a number of architectural structures, including the walls of the rooms and pools that made up the baths area, which was split into a hot and a cold zone. There are also remains of elements that held up the roof, as well as stairs, pipes, fountains, sewers, ovens and hypocausts.

The coatings that covered the wall surfaces and the flooring preserved in situ, though in fragments, indicate the sumptuous nature and rich decoration of the complex. Highlights include the fresco murals, Alcover stone claddings and slabs, marble claddings of various colours, tiled coatings, ceramic flooring and some remains of polychrome opus tessellatum mosaics.

Intervention

The conservation-restoration tasks focused on cleaning up the spaces, stabilising the materials’ deterioration process and improving interpretation of the archaeological remains. Above all, work was carried out on the different kinds of coatings preserved on the walls and floors, and occasionally on the wall structures themselves.

Though the basic activities were similar in many ways, broadly, different treatments were carried out on ashlar and/or brick walls and on different types of coatings (opus signinum, marble claddings, mosaic tesserae, stone slabs and murals).

The most important phases of the intervention can be summarised as cleaning, consolidation and material reintegration. In all cases, materials compatible with and similar to the originals were used. The application procedures and methodologies, as well as the exact composition of the materials, were determined by the results of the preliminary studies carried out before the restoration began.

The interventions carried out must be accompanied by constant maintenance of the whole area, so that the effects of the complex’s exposure to atmospheric and environmental conditions can be counteracted.

— Neus Casal and Rudi Ranesi

The mural paintings preserved in the far south-west of the ambulacrum (entrance area to the baths) after the intervention

Restoration

Coordinator: Rudi Ranesi (Arcovaleno Restauro, SL), Neus Casal (documentation), Carlos Alías, Maria Cardenal, Gianpiero Lauriola, Lorenzo Masi and Melitón Sánchez

Photographs

Verònica Moragas

Year of restoration

2016

Recomposition process of the canal that carried water from the north of the site to the bath area

General view of the natatorium pool and the frigidarium pool after the intervention

Process of cleaning, reorganising and rearranging the ceramic floor of the caldarium

Conservation-restoration intervention on the temples in the sacred area of the archaeological site in Puig de Sant Andreu, Ullastret

The sacred area of the settlement is located at the highest point of Puig de Sant Andreu, where the remains of temples A and C are preserved. The temples date from the 4th and 3rd centuries BCE, and they are among the few buildings of this nature in Iberian culture. Archaeological interventions in this area started in 1955 and finished in 1960 with a restoration of the remains.

The aim of the restoration was to study and document the alteration factors and indicators that contributed to the deterioration of the walls and the preserved coatings, as well as to know the state of the remains at the time of their excavation, before the restoration intervention of 1960. It was also necessary to stop the active alteration processes in order to minimise future deterioration and to work on the project to improve the system of presentation of the whole.

State of conservation

The remains are located outdoors; therefore, they are continuously exposed to climatic agents and thermal and humidity contrasts, which triggered much of the detected pathologies. It should also be noted that the temples are located in the middle of a an area with significant visitor traffic, so they had also suffered anthropogenic damage.

The documented alterations in walls and coatings were broadly as follows: widespread presence of biogenic deterioration; disintegration; total or partial losses; cracks and fissures; cavities; detachment of wall coatings; remains of old cements; and misplacement or displacement of most of the ashlars at the top of the walls of temple A.

Intervention

The conservation processes included, first of all, exhaustive photographic and cartographic documentation, and the

Material/Technique

Walls made of different-sized local sandstone ashlars, which form a polygonal surface. A wall coating made of chamotte is preserved in temple C

Date/Period

4th and 3rd centuries BCE

Dimensions

Approximate surface area: temple A 40 m² and temple C 96 m²

Location

Iberian settlement of Puig de Sant Andreu, Ullastret (Baix Empordà county). Archaeology Museum of Catalonia-Ullastret

Coordination

Maria Molinas (Àbac Conservació-Restauració, SL)

Restoration

Sílvia Llobet and Maria Molinas (Àbac Conservació-Restauració, SL) and Gemma Piqué

Year of restoration

2016

elaboration of individualised files integrated into a database, in order to bring together all the data on each structure. An interdisciplinary collaboration was also carried out to study the original materials.

As stated above, most of the ashlars at the top of the walls of temple A were misplaced or displaced. With the help of both the archaeologist team and old photographs, we could verify which ashlars were part of the original walls and which were away from their original location, bound with cement. We decided to dismantle the non-original parts, while the original elements of both temples underwent processes of cleaning and removal of cements, as well as biocide treatments. Cracks, flaking and air pockets were consolidated using lime mortars. The structural consolidation of the top of the walls was also achieved with lime mortar, while taking the circulation of rainwater into account.

The chamotte coatings of temple C were cleaned and underwent biocide treatments and removal of all reintegrated cements, before being secured with hydraulic mortar injections. All damaged edges were bevelled with hydraulic mortar.

The intervention and the examination of the original materials have enabled us to recover relevant data, which has generated a new architectural understanding of the temples. What is more, we have been able to compare with and finetune the chronology previously put forward and to identify the construction technique of the temples. An important fact to mention is that the use of lime mortar as a binding material for the original stone ashlars was documented, which is rare in the context of the archaeological site and the Iberian architecture of that time.

— Maria Molinas

State of the temples after the conservation intervention

 Close-up of the mechanical cleaning work and biocide treatment on the ashlars in the walls

 Bevelling of the chamotte coatings with hydraulic mortars Initial state of the temples

Object

Set of personal and horse adornment items and weaponry elements. One hundred and forty-eight objects: two parts of a sword blade fragment, a greave, nine flanged axes, four belt buckles, seventy-seven bracelets, fifty-two circular buttons with a ring, two badges with a ring, a fragment of circular plate and a piece of bronze smelting remains

Material/Technique

Bronze/smelting. The pieces were finished with thermal (annealing and tempering), mechanical (hammering and forging) and ornamental (use of a marking gauge, fretwork, engraving with a burin or chisel) treatments

Title/Topic

Llavorsí trove. Bronze deposit of Llavorsí

Date/Period

8th to 7th centuries BCE

The bronze deposit of Llavorsí dates from the 8th and 7th centuries BCE and it is the most important collection made of this material (148 pieces) ever found in a deposit in Catalonia.

Josep Gallart, archaeologist for the Territorial Services of Lleida, who studied said place and its objects, explains in his study «The bronze deposit of Llavorsí. Pallars Sobirà1» that the discovery of the deposit was accidental. It was found in 1985 by a collector of weapons from the Spanish Civil War who was looking for pieces using a metal detector. The hiding place was located on a slope at an altitude of 1,600 m, near the peak of Urdosa, 4 km away from Llavorsí.

The metals were piled up in no particular order and were surrounded by slabs, without any wrapping or container. The collection was made up of personal and horse adornment items and weaponry elements: a two-part fragment of a sword blade, a greave, nine flanged axes, four belt buckles, seventyseven bracelets, fifty-two circular buttons with a ring, two badges with a ring, a fragment of circular plate and a piece of bronze smelting remains.

Most of the objects come from central-eastern France. In view of the typology of the pieces, and taking into account the fact that many of them are fragmented and the piece of smelting remains found, it is believed that all these objects were the raw material used by a travelling metallurgist, who had hidden the pieces to re-smelt them.

Due to its singularity, the collection is held at the Museum of the History of Catalonia and can be seen in the permanent exhibition. This collection of bronze items has been restored twice since its discovery in 1985. In 1991, it was mechanically cleaned, mainly to remove its archaeological sediment in order to allow the pieces to be studied. Later, in 2011, a second conservation-restoration intervention is documented, where the collection was chemically cleaned. In 2015, due to the change of display case that housed the set of bronze items, the Museum of the History of Catalonia —with guidance from the CRBMC— examined the 148 objects exhaustively. Some of the objects were fractured and, even though it could be appreciated that the support structurally retained a good metal core and very homogeneous layers of carbonates, it had been affected by corrosion between the metal core and the surface. It was decided to carry out a curative conservation intervention, with the aim of guaranteeing the preservation of each of the objects for display.

Action was systematically taken on all pieces. It consisted of removing purified wax from the surface (which was detected during the analyses) and then performing a test for the presence of active corrosion. Lastly, a mechanical cleaning to remove sediment residues and corrosive products was executed. The cleaned pieces were immersed in a hydroalcoholic solution with two inhibitors in order to slow down the corrosive process. A protective layer of acrylic resin, with the addition of an inhibitor, was also applied to insulate the pieces from the environment.

— Carolina Jorcano

1 / Excavacions arqueològiques a Catalunya, núm. 10. DGPC, Archaeology Service of the Diputació de Lleida, Department of Culture of the Generalitat de Catalunya, pp 11–13 and 192–198

Close-up of the original incised decoration on one of the planoconcave bracelets after the conservationrestoration intervention

Location

Archaeology Museum of Catalonia, Barcelona (Barcelonès county)

CRBMC Register NO

From 12553.1 to 12553.148

Years of restoration

2016-2017

Image of the set of 148 objects that make up the bronze collection from Llavorsí after the conservationrestoration intervention Curved belt plate split into three parts before and after the conservationrestoration intervention Fragment of an ornamental circular plate with incised decoration before and after the conservationrestoration intervention

Object

A ceremonial dish, three zoomorphic supports, a wall sconce, a ring and two jugs

Material/Technique

Bronze/smelting, hammering, welding, casting in mould

Title/Topic

Objects for ceremonial and daily use, furniture decoration and personal adornment

Dimensions

Dish (height 4.2 cm, max Ø of the rim 17.6 cm and max Ø of the base 16 cm); leg in the shape of a bird of prey’s foot (5.5 × 4.2 × 6.5 cm); leg in the shape of a feline paw (2.5 × 2.5 × 2.8 cm); lion head-shaped wall sconce (4 × 5.7 × 5.7 cm and max Ø 5.5 cm);

The renovation of the building of the National Archaeological Museum of Tarragona (MNAT) and the consequent dismantling of the permanent exhibition rooms, as well as the transfer of all the exhibited heritage to the new temporary museum or storage spaces during the works, led to a thorough examination of every piece.

It was necessary to study and determine the state of conservation of each object and to establish priorities in terms of conservation-restoration interventions. In this context, the Centre for the Restoration of Artefacts of Catalonia received eight bronze metal objects with alterations that were typical of the corrosion of metal, which needed intervention. This way, their future conservation would be guaranteed, and the pieces could be integrated into the new design of the MNAT.

All the pieces come from archaeological excavations carried out in different parts of the Roman city of Tarraco (13081: Forum of the Colony area; 13082: Convent of Santa Clara; 130823: Plaça de Prim; 13084: unknown origin; 13085: Camí de l’Arrabassada) and at different historical moments.

In 1864, the two jugs and the dish for ceremonial use were recovered while an old well, 30 m deep, was being filled in, on Carrer de Gasòmetre in Tarragona. They were discovered along with other similar objects (eleven other jugs, an amphora, three buckets and a dish) and sacrificial utensils (knife, axe and shovel to burn incense). Some of the pieces from this find were restored at the CRBMC by M. Àngels Jorba in 1990.

State of conservation

The state of conservation differed from one piece to another: the two jugs had the worst state of preservation, as they showed significant losses of metal support and there was evidence of a large degree of corrosion.

In general, all the pieces had remnants of hardened sediment on the surface as well as metal corrosion with more or less dispersed focuses of chlorides. They also showed a relatively thick homogeneous patina of a greenish blue hue, typical of carbonation mechanisms, and a reddish one below, which is typical of the oxidation of metal. The pieces showed mechanical alterations due to metal corrosion: surface deformations and losses of material.

Intervention

The conservation-restoration criterion was to respect the patinas produced by the passage of time. Action began on each artefact with a mechanical, dry removal of the hardened sediment and of the loosest corrosion products using a brush, scalpel and dental lathe. Microblasting and chemical cleaning with swabs were also used as cleaning methods for the ceremonial dish.

The pieces that were confirmed to have active corrosion in a previous test were stabilised with the most appropriate traditional procedures (Organ method and Rosenberg method), depending on the type of corrosion: if it was more widespread on the piece’s surface or if it had occasional scattered corrosion focuses.

Resin and/or epoxy putty was used to adhere fragments and reintegrate material on the vases. Some fragments had to be reinforced with fibreglass inside the piece.

In order to stop or delay the chemical reactions that could occur in the pieces due to interaction with the environment, a hydroalcoholic mixture of two inhibitors and, later, a protective layer, were applied to the objects. This procedure was done by immersion or with a brush, depending on the piece, using a very diluted acrylic resin to insulate the metal surface of the pieces from harmful environmental agents.

— Laia Contreras and Carolina Jorcano

Image of the lion head ornament before and after the conservationrestoration intervention

leg in the shape of a lion’s paw (2.5 × 2.7 × 3.2 cm); jug with handle (height 22 cm, max Ø of the opening 8 cm, max Ø of the base 6.4 cm, max Ø of the body 11.8 cm); vase with a channelled spout (height 17.3 cm, max Ø of the base 7.4 cm, max Ø of the body 13.4 cm) and ring (max Ø 2.2 cm and max interior Ø 1.9 cm)

Origin

Various, from the Roman city of Tarraco, Tarragona (Tarragonès county)

CRBMC Register NO

3667, 3669 and from 13080 to 13085

Restoration

Directed by: M. Àngels Jorba; restoration: Laia Contreras and Carolina Jorcano

Year of restoration

2017

Photograph of the three zoomorphic supports after the conservationrestoration intervention Close-up of where the handle of the jug once was, with a medallion depicting a head, after cleaning, corrosion inhibition and the application of a protective layer

Image of the two jugs after the conservation-restoration intervention

Material/Technique

Bronze

Title/Topic

Women’s personal adornments and fragments of bronze vessels

Date/Period

Between the beginning of the Early Iron Age and the Iron Age. Between the 7th and 6th centuries BCE

Location

Territorial Services of Lleida (Segrià county)

CRBMC Register NO

13092

Archaeological coordination

Josep Gallart (Territorial Services of Lleida)

In mid-August 2016, a compact mass, made up of a conglomerate of bronzes and very hardened earth, was accidentally recovered from the interior of a ceramic vessel buried in a meadow in Colomina de Bor. Other bronze elements that were part of the same deposit were also recovered around it.

First of all, an emergency archaeological intervention was carried out to document and recover the ceramic vessel, which was still preserved in its original position. The intervention was led by the Archaeological and Palaeontological Service (SAP) of the Department of Culture of the Generalitat.

The metal materials were then transferred to the Centre for the Restoration of Artefacts of Catalonia (CRBMC), so that they could be treated and restored.

The conservation-restoration process

First of all, the micro-excavation of the compact mass of metals and earth was carried out. The mass had been extracted from the interior of the ceramic vessel at the time of its discovery. It should be noted that the intervention was extremely laborious and delicate, because the conglomerate was very solid and hardened.

Once the objects were released, the ceramic vessel was restored, which involved: manual cleaning of the limestone crust; consolidation of the fragments, especially the cracks, in order to stick them together with nitrocellulose adhesive; gypsum-plaster reintegration; and finally, pictorial reintegration.

Great care had to be taken during the restoration of the metal objects: the texture of the mass was so firm that the pieces contained in the vessel could not be appreciated on the X-rays that were carried out. At first, a dry and mechanical disintegration of the earth was attempted, but seeing that the earth was too hard, we decided to wet it in order to soften it. Palettes and syringes with water and alcohol were used, and the mud was removed using a scalpel and punches. At that time, the composition of the bronze conglomerate could begin to be appreciated. The thickest part of the conglomerate was made up of small chains that were highly intertwined and compressed, as well as compacted and fused together.

The ultrasonic cleaner was a very useful addition to the excavation and cleaning process. Its vibration offered a smooth movement that acted inside the mass. The treatment and the use of a punch helped to release the objects. The process was carried out very slowly to avoid any breakage, especially in the chains, which were very thin and weak. The ones that did break, however, were kept in place and were threaded with fishing line to maintain the position of each one.

Once the conglomerate had been disassembled and the pieces had been removed, we saw that there were no problems in terms of state of conservation. The patinas had not been able to develop due to the lack of air during all those years that the object had been buried.

The restoration process continued with brushing with the metal lathe and fibreglass. Finally, consolidation was achieved by immersion with a synthetic acrylic resin, which provides stability in terms of conservation of the pieces.

— CRBMC

This article was prepared by the writers at CRBMC based on the intervention report written by the conservation-restoration coordinator, M. Àngels Jorba (CRBMC), and the article by the territorial archaeologist for the Generalitat de Catalunya, Josep Gallart, in: Tribuna d’Arqueologia (blog of the Archaeological and Palaeontological Service of the Department of Culture) in the lecture «The bronze deposit of Colomina de Bor (Bellver de Cerdanya, la Cerdanya)» given on on 30 May 2018.

Years of restoration

2016-2017

Chest pin with chains and rings after the conservation-restoration intervention

Close-up of the chest pin with chains after the conservationrestoration intervention

Conservation-restoration intervention on the Greco-Roman archaeological site of Empúries. Archaeology Museum of Catalonia-Empúries

Material/Technique

Various

Date/Period

2nd century BCE to 2nd century CE

Dimensions

Neapolis: 4 ha; Roman city: 22 ha (only 20% of which has been excavated)

Origin

Archaeology Museum of Catal-

Location

Archaeological site of Empúries, L’Escala (Alt Empordà county)

CRBMC Register NO

13222

Coordination

Sílvia Llobet (Àbac Conservació-Restauració, SL) and Pere Rovira (CRBMC)

Restoration

Sílvia Llobet and Maria Molinas (Àbac Conservació-Restauració, SL); Laia Abelló, Gemma Piqué,

Since 2015, a protocol of conservation-restoration works has been established at the Greco-Roman site of Empúries. The aim of the protocol is to guarantee the safeguarding of the preserved structures of both the Roman city and the Greek city or Neapolis.

Of the different urban phases, structures of both private and public spaces are preserved. They are made with various construction techniques and have decorative features such as pavements, mosaics, murals and sculptural elements. These are subject to numerous risks, e.g. exposure to climatic agents, biodeterioration or the large annual number of visitors.

The works we present are included in the Conservation Plan of the Archaeological Site of Empúries, which is promoted by the Centre for the Restoration of Artefacts of Catalonia (CRBMC) and the Archaeology Museum of Catalonia-Empúries.

State of conservation

The most serious problems that affect the large number of preserved structures are those that cause structural weakening. These problems can occur for different reasons:

a) removal of the lime in the walls produced by the continuous washing of rainwater when the rooms are not refilled to the level of circulation. b) detachment of construction elements, such as ashlars, caused by anthropogenic action or by loss of the joint mortar. c) disintegration of the building materials used to make the rammed-earth walls.

Furthermore, biodeterioration is an important factor of deterioration, whether it is caused by the growth of trees and plants, the presence of dens of small mammals, or the nests or colonies of insects and isopods.

In addition, there are problems related to the materials used in previous interventions. For example, decorative elements preserved in situ have been restored on several occasions during the 20th century, usually using inappropriate materials such as cement, and they are currently very damaged. We have also found applications of consolidating products, mainly acrylic resins, which generate yellowing and considerable superficial losses of matter.

As for the flooring and mosaics, the most serious pathology is the proliferation of microorganisms, which has caused serious problems with warping, separation of layers and disintegration of both mortars and stone elements. In the case of the murals, the most serious problem besides biocolonisation has been the interventions carried out with cement, which have weakened the original mortars and caused detachment, disintegration and separation of layers.

Documentary work on the state of conservation of one of the preserved bichrome mosaics in the Roman city

Emergency conservation and cleaning work on a bichrome mosaic from house 1 in the Roman city

State of conservation study on decorated mortar flooring in the Neapolis

Intervention

In order to manage such a complex archaeological site —which is large and includes many preserved structures— first it was necessary to make a general diagnosis of its state of conservation and the most serious risks that needed to be addressed.

At the same time, a maintenance protocol was established, which divides the site into five zones —forum, house 1, house 2, public baths of the Roman city and structures of the Neapolis— and action is taken three times a year in each of those areas. Cleaning is done to prevent the accumulation of dirt; stagnant water is removed after heavy rains; biocide treatments are carried out, if necessary; and a checks on the state of conservation using forms, photographs and maps are made. It is essential to perform these actions in order to ensure annual monitoring of the evolution of the ruins, and to act quickly in case an emergency intervention is required.

Preventive conservation activities are also carried out to ensure the good condition of the paving and murals. These activities focus on studying and developing control strategies for the impact of microorganisms; providing covering during the colder seasons; and monitoring areas that are sensitive to changes in temperature and relative humidity. In the case of structures, earth is added around undermined walls and pools of water and plant growth are controlled.

Every year, in addition to the aforementioned work, restorations of structures are also carried out. The structures are selected according to their state of conservation, be it for the removal of old restorations, for new archaeology campaigns or for the museumisation of new spaces within the itinerary. For example, in 2015, mortar paving with tile decoration and the walls of the baths of house 2B were treated. In 2016, two white-background mosaics with black borders and decorated mortar paving in house 1 were restored. In 2017, action was taken in a room containing a mural and two-tone mosaic and on two two-tone mosaics of house 1. In 2018, work was performed on all the paving intact in the house of the Tuscan atrium and in what is known as the house of Agathos Daimon, in the Neapolis. Finally, in 2019, action was taken on the paving and coverings in the Late Antique basilica of the Neapolis.

 Restoration work carried out in 2015 on the walls and coverings of the baths in house 2B in the Roman city  Restoration work carried out in 2016 on flooring in house 1 in the Roman city  Restoration work carried out in 2018 on the house with the tetrastyle atrium in the Neapolis

Restoration work carried out in 2018 on the decorated mortar flooring in the house with the Agathos Daimon inscription in the Neapolis Restoration work carried out in 2019 on the marble chip flooring in the Neapolis basilica

Object

Tableware, kitchen utensils, storage recipients, leisure objects and everyday objects

Material

Ceramic, glass, metal (iron and bronze) and bone

Technique

Wheel, glazing, casting, forging, blowing, sculpting, lustring

Title/Topic

Everyday objects from Montsoriu Castle

Origin

Montsoriu Castle, Arbúcies (Selva county)

Location

Ethnological Museum of Montseny – La Gabella, Arbúcies (Selva county)

CRBMC Register NO

10704 to 10742; 10817 to 10854; 11144 to 11174; 11367 to 11383, and 11948 to 11976

Montsoriu Castle is known as the most important Gothic castle in Catalonia. It is located in Montseny Natural Park, at an altitude of 633 m, between the towns of Arbúcies and Sant Feliu de Buixalleu in the county of Selva, and overlooks much of the area.

Research, examination and restoration tasks have been going on continuously for over twenty years, following archaeological excavations in 1993, with work, collaboration and participation from public and social organisations, the professionals at the Ethnological Museum of Montseny – La Gabella, archaeology students and the young people on the Youth Department’s work stays. This has led to the reconstruction of the castle’s history, as well as the recovery of its architecture and of material remains – of manufactured objects, flora and fauna – to achieve better, more in-depth overall knowledge of life in the castle. Over the years, it evolved from a rock castle in the tenth and eleventh centuries, to an impenetrable fortress in the thirteenth century and to a residential Gothic palace in the fourteen century occupied by the viscounts of Cabrera, until it went into decline and was abandoned in the sixteenth and seventeenth centuries.

There was a key point in this process of getting to know the castle: at the end of the excavation campaign in 2007, a cistern was taken down in the bailey, and a deposit of everyday equipment from the castle was found. These approximately four hundred objects included tableware, kitchen utensils, storage recipients and objects like flabiols, dice, coral beads, lanterns, thimbles, buckles and knives, as well as a great amount of animal remains. Some old documents refer to this deposit and indicate that, in 1570, the procurator of Viscount Luis Enríquez of Cabrera ordered the castle guard to empty it and take out all the goods inside, before the imminent takeover of the new owner, the count of Aitona.

Close-up of the carved head on a bone pin from the fifteenth–sixteenth century CE, after the conservationrestoration intervention

Intervention

To make this material exhibitable and visitable, the Centre for the Restoration of Artefacts of Catalonia took charge of conserving and restoring around one hundred and seventy pieces between 2008 and 2015. Most of the materials were ceramic, but there was also metal, glass and bone.

In the case of the pottery (most of which arrived assembled), the intervention consisted of dismantling them, removing chlorides, adhering fragments, and volumetric and chromatic reintegration. The glass pieces were also cleaned and adhered and underwent volumetric reintegration. Meanwhile, remains of archaeological sediment and layers of corrosion were removed mechanically from the metals, and an inhibitor and a protective layer were applied.

The intervention on the bone objects consisted of removing sediment and dirt. In general, the pieces presented a good state of conservation, and many were practically whole, in large fragments. This is down to the fact that there may still have been water in the cistern, which would have cushioned the objects’ fall.

Nonetheless, the lustreware was in a surprisingly poor state of deterioration. Therefore, in parallel to the restoration, a study was carried out with Dr. Trinitat Pradell (UPC), which revealed an alteration caused by the wet, possibly acidic environment in the cistern and the phosphoric acid from the bone remains.

From the restoration of the objects found in the cistern, around fifty tableware services have been recorded, including plates, bowls, serving dishes, pitchers, jugs, jars, cruets and glasses that were likely used for celebrations, due to their sumptuous nature. Some pieces were imported, including earthenware decorated in blue (workshops in Barcelona), lustreware (producers in Valencia), and polychromed earthenware, which was highly appreciated at the time (workshops in Montelupo and Tuscany, Italy). The kitchen utensils and storage recipients (pots, lids, roasting tins, basins, jars, washing-up bowls, etc.) were reduction-fired (black) or oxidation-fired (red, honeycoloured tones, similar to those still produced in the pottery workshops of Breda). They were used to cook and store fish bought and used for everyday food in the castle (northern pike, tuna, European conger, gilt-head bream, mackerel, cod, etc.), pork, lamb, goat, birds (pigeon, chicken, goose, partridge), fruit (especially grapes) and nouveau wine. The restored pieces are currently on display in a room dedicated to Montsoriu Castle in the Ethnological Museum of Montseny – La Gabella, and they constitute the most significant archaeological collection of Catalan pottery in Catalonia, dating from the last quarter of the fifteenth century and the first third of the sixteenth century.

Restoration

Directed and coordinated by: M. Àngels Jorba; restoration: Carolina Jorcano (team leader) and Carolina Bernal, Mireia Borgoñoz and M. Àngels Jorba; interns: Xisca Bernat, Anna Bertral, M. Magdalena Escalas and Bernat Font

Years of restoration

2008-2015

Image of the first set of pieces from Montsoriu Castle restored at the CRBMC, made up of various ceramic pieces from the table service, kitchen utensils and storage containers, everyday metal objects (a lamp, a knife, a thimble, a sheath and sixteen coins), two glasses, and the base of a glass

North African, green, wheel-thrown pottery from the fifteenth–sixteenth century CE, made up of a multitude of fragments, before and after the conservation-restoration intervention Glass cup with two handles before and after the conservation-restoration intervention

Material/Technique

Attic red-figure pottery

Title/Topic

Red-figure painted pelike/red-figure painted bell krater

Date/Period

5th and 4th centuries BCE

Origin

Greco-Roman site of Empúries, Empúries (Alt Empordà county)

Location

Archaeology Museum of Catalonia, Empúries, L’Escala (Alt Empordà county)

To coincide with the renovation of the Archaeology Museum of Catalonia (MAC-Empúries), it was decided that we would update the intervention criteria for an Attic red-figure ceramic pelike, restored in 1906, and an Attic red-figure ceramic krater, which had already undergone a restoration intervention but needed updating.

Object description: pelike and krater

A pelike is a large recipient with a base that was used to contain liquids, especially wine.

On one side, this artefact is decorated with a winning chorus in a dithyramb competition at the Thargelia in honour of Apollo, which took place in Athens. The other side portrays a fight between Centaurs and Lapiths at the wedding of Pirithous and Hippodamia. The characters can be identified by the inscriptions with their names next to the depiction.

The bell krater is a recipient in the shape of an inverted bell with two handles pointing upwards, supposed to contain a mixture of water and wine. It was placed on the ground or on a platform at meal times, and the cupbearer (pincerna or pocillator) would serve the guests from it.

On one side, there is a woman dressed in a peplos sitting and playing an aulos, two men lying on a klinē and a woman carrying a tray. The other shows three men dressed in himations standing and talking.

Pelike. Close-up of an inscription of the name of the person depicted

State of conservation

Although it appears fully intact, only 45% of the original pelike is preserved. The rest is from the previous intervention.

This laborious intervention was not entirely successful for the following reasons:

• it increased the artefact’s weight considerably; • it led to some fragments being slightly uneven; • the material reintegration overlapped the original at some parts, while at others, it was recessed and irregular; • the pictorial reintegration of the restored area overlapped the ceramic at several points, and made it difficult to see the scenes and the overall object; • the beeswax, which was applied as protection and had darkened over the years, concealed the original appearance of the piece.

As for the bell krater, the following alterations were detected:

• though it respected the shape, the previous intervention led to fragments being slightly overlapping or having little contact between them (open); • the material reintegration (done with white gypsum) overlapped the original at several points, while at others, it was recessed and irregular; • the colour applied made it hard to see the object properly, and a protective layer made the scenes slightly glossy, which was not the case in the original (the black varnish was glossy, but the red figures were matte).

Intervention

Following the preliminary studies on both artefacts, the new intervention consisted of taking the pieces apart completely, cleaning the fragments, removing the protective layer from the surface, putting them back together again by adhering the different fragments, and reintegrating the various hollows.

In the case of the pelike, the volumetric reintegration was carried out with gypsum, then it was painted, while coloured gypsum was used on the bell krater.

On the krater, some hollows were not filled in, so that an analysis could be carried out on the clay one day, if necessary.

All in all, the historical, artistic and aesthetic value of these artefacts has been restored and they are ready for exhibition.

— Laia Contreras and M. Nieves Marí

Years of restoration

2014-2015

Pelike. After the conservationrestoration intervention Krater. After the conservationrestoration intervention

Krater. Close-up of the previous intervention, when the CRBMC arrived

Two opus vermiculatum Roman emblems of the Archaeology Museum of Catalonia-Empúries: The Mosaic of the Partridge and the Mosaic of Iphigenia’s Sacrifice

Material/Technique

stone

Title/Topic

Mosaic of Iphigenia’s Sacrifice: mythological figurative artwork;

Dimensions

Mosaic of Iphigenia’s Sacrifice: 56,6 × 59,8 cm (mosaic) and 64,1 × 61 cm (stone base); Mosaic of the Partridge: 32 × 32,5 × 0,65 cm

In 2014, the Archaeology Museum of Catalonia-Empúries proposed the restoration of several pieces of great importance from its collection. The pieces were discovered in excavations carried out more than a hundred years ago and they had been restored during the first half of the 20th century, following the criteria of the time. The objects presented precarious and aged restorations that needed to be renewed.

Two of those pieces were two vermiculatum: Roman emblems: The Mosaic of the Partridge and the Mosaic of Iphigenia’s Sacrifice. The emblems formed the main part of a mosaic and were located in the centre of the composition. They were made separately from the rest of the pavement, in the workshop. They were shaped like a small tapestry and were made of tiles (small cubes made of materials such as marble or other stones, ceramic, glass or glass paste, all of them in various shades). It was attached to a ceramic or marble plate, on which the tiles were fixed with lime mortar. It had a figurative theme. It was later inserted in situ in the rest of the pavement, which had larger tiles and a generally geometric decoration. The opus vermiculatum emblems were characterized by the use of very small tiles, of about 4 mm on each side. The tiles were arranged following the lines of the figurative motifs (musculature, folds in clothes, leaves of the trees...) as if they were worms (from the Greek vermis, «worm»), which made the details, the incidence of light and the volumes be very well defined. They were a perfect image of the represented object. They were probably inspired by murals, and they had Hellenistic influences. The repeated use of some of them in later pavements indicates that they were highly valued artworks.

The Mosaic of the Partridge probably comes from Roman house number 1 of the archaeological site. It was bought and deposited in the Archaeological Museum of Empúries in 1913.

State of conservation

The naturalistic-themed emblem shows a partridge pulling a necklace from a jeweller. It is preserved on the original stonesupport. Its state of conservation at the time of the restoration intervention was good, although only 75% of the piece was preserved.

In a previous restoration intervention, the gaps of the tiles and the stone of the support had been reinstated with gypsum, and the remaining fragments had been adhered to them.

Intervention

The proposal for the current intervention included the removal of gypsum —which was not on the original piece— and its replacement with lime mortar. However, while the gypsum was being removed, it was observed that remains of the original mortar that fixed the tiles to the stone support were

Opus vermiculatum emblemata known as the partridge mosaic, before and after the conservationrestoration intervention

Location

Archaeology Museum of Catalonia-Empúries, l’Escala (Alt Empordà county)

Restoration

Carolina Jorcano

Years of restoration

Mosaic of the Partridge: 2015; Mosaic of Iphigenia’s Sacrifice 2017

Mosaic depicting the sacrifice of Iphigenia after the conservationrestoration intervention

Cleaning of the tiled surface of the mosaic depicting the sacrifice of Iphigenia in order to remove the layer of wax and dirt, through the application of an emulsion Close-up image of the smaller tesserae and the preserved remains of the layers of original mortar where they are attached

UV photograph of the mosaic depicting the sacrifice of Iphigenia, showing the reintegrations of polychrome gypsum carried out in a previous intervention (in greenish tones), in the areas where the original mosaic tesserae were not preserved

preserved. After that, the option of leaving them visible was considered.

To prevent the tiles from coming loose, they were consolidated with a lime mortar bevel. Lastly, the surface of the tiles and the stone slab were cleaned, which made them regain their original hue. The base fragments were attached to it using a more reversible adhesive.

In 1848, the Mosaic of Iphigenia’s Sacrifice was found inside an unexcavated house in the archaeological site of Empúries. It was discovered by some residents of l’Escala who owned the house. At the beginning of the Spanish Civil War, after having been on sale without any interested buyers, the mosaic was removed and taken to the Archaeological Museum of Barcelona to avoid the risk of losing it. Three years later, in 1940, the mosaic was restored there.

A secondary reinforced concrete support was made for it, and the tile losses were restored with plaster, reproducing their shape and colour. The mosaic dates from the 1st century BCE and depicts a theatrical scene of Iphigenia’s sacrifice. It possibly represents Euripides’ play.

The general condition of the mosaic was quite good, except for the green, black and brown tiles, which were very degraded. Previous studies performed with UV and X-ray photography, as well as the analyses that were carried out, ruled out that the alteration of the tiles was caused by the degradation of the cement or the metal mesh of the secondary support. This made it possible to determine what needed to be done for their conservation (also taking into account the risk involved in removing them) as well as for the conservation of the polychrome gypsum reintegrations, since removing them would supose the loss of information of the figurative scene. The intervention consisted mainly of cleaning the surface of the tiles, reducing and chromatically retouching the small gypsum reintegrations, replacing the gypsum with lime mortar in the large gaps and adhering and reintegrating the fragments of the preserved stone slab, to be able to insert the mosaic and return it to its original appearance.

— Carolina Jorcano

The village of Santa Creu de Rodes (11th-16th centuries) is located in the municipality of Port de la Selva (Alt Empordà county), one kilometre away from the monastery of Sant Pere de Rodes and next to the church of Santa Helena, which currently is the only building in the settlement still standing.

The village was crossed by a cobbled path that connected two towers. These were located at the entrances to the village, to the north and south of the centre. Both quadrangular-based towers acted as the main entrance to the village.

When the village was left completely uninhabited, the church became the sanctuary of Santa Helena. Its last gathering was held on 3 May 1880.

Recent archaeological interventions have confirmed the existence of a settlement dated between the 11th and 16th centuries, and a necropolis dated between the 8th and 9th centuries. Inside one of the rooms of the village’s houses, a medieval tombstone made of slabs and a silo excavated in the rock were discovered, and are still visible.

In the 2007 excavations, five anthropomorphic tombs were documented. They were in poor condition and held few bones. It can be assumed that the construction of the village’s houses was the reason why the tombs were damaged. Utensils for everyday life, such as a hoe, a belt buckle and fragments of pottery, were also found in that same building.

State of conservation

The restoration has been executed in different phases and batches, depending on when the excavated material arrived at the Centre for the Restoration of Artefacts of Catalonia (CRBMC). Work has been carried out on more than one hundred and fifty-five pieces.

These are metal objects, mostly made of iron (nails, field tools,

Material/Technique

Iron, bronze, lead and glass

Date/Period

11th to 16th centuries CE Medieval period

CRBMC Register NO

Various

Restoration

Pol Camps and M. Magdalena Gómez

Years of restoration

2008-2011 and 2016

locks and keys) or bronze (nails, studs, coins, decorative sconces and plates), and to a lesser extent, lead and silver. Work was also carried out on a few glass and bone objects.

In general, all the material was covered with earth, dust and other deposits. Some of the iron objects were fragmented but complete, while others were incomplete. They all had some degree of oxidation, which worsened the fragility of the metal and made it brittle.

Alteration was observed in some of the bronze objects, in the form of superficial stains or green spots (chlorides), which were sometimes dusty. This alteration could weaken the metal until disintegrating it in the most extreme cases. Most were whole, but some, in addition to being fragmented, were incomplete.

Intervention

The restoration and the plan of action depended on the fragility of the object. The first step was drying to extract the moisture, followed by a surface mechanical cleaning, neutralisation, joining the fragments, reintegration of the support, and consolidation, or application of a final layer of protection.

In 2016, a new protocol for the stabilisation of archaeological irons was developed in the Archaeology Laboratory of the CRBMC. Extracting the chlorides from inside the iron objects until they were left at very low chloride levels was considered essential, as these are the main destabilisers of these kind of pieces.

The most historically valuable iron objects from the 2012 and 2014 excavation campaigns were treated using this system. Over the course of four weeks, the objects were subjected to successive electrolyte immersion baths, until the concentration of chlorides in solution was equal to or less than 25 mg/l.

— Pol Camps and Magda Gómez