*MSc Cultural Heritage Materials & Technologies (University of the Peloponnese) *BS Conservation of Antiquities & Works of Art (University of West Attica) *Member of the conservation team of Korseai Institute in the Fournoi project *Resent research: Physical, chemical, mechanical characterization of a charred medieval shipwreck
In 2008, a late-12th-century merchant ship was discovered off the commercial port of Rhodes. The ... more In 2008, a late-12th-century merchant ship was discovered off the commercial port of Rhodes. The vessel caught fire before sinking and thus numerous hull timbers were found charred. Three main degrees of charring have been recorded that presented major chemical differences which indicated different conservation requirements. This study investigated the correlation between the chemistry of the waterlogged timbers and their physico-mechanical properties, to assist in the development of an appropriate conservation strategy. Scanning electron microscopy documented the morphology of charred, semi-charred and uncharred samples. Moisture content and density were measured gravimetrically, while porosity was evaluated using mercury intrusion porosimetry. Hardness was assessed using a modified Janka test and a penetrometer. The results obtained showed that differences in chemistry were highly correlated to the physico-mechanical properties of the timbers. The charred wood presented the lowest moisture content, shrinkage and porosity among the three charring conditions and it also had the highest density, Janka hardness and resistance to penetration. The exact reverse properties were recorded for the uncharred material, which was typical of badly preserved, waterlogged wood. The semi-charred wood presented transitional features. These results indicate that the uncharred wood is in need of consolidation, in contrast to the charred and semi-charred material, which may be left to air-dry untreated.
In 2008, a medieval wooden shipwreck was discovered at the port of Rhodes, Greece. The shipwreck ... more In 2008, a medieval wooden shipwreck was discovered at the port of Rhodes, Greece. The shipwreck was party burned, presenting a challenge for conservators, as uncharred, semi-charred and charred waterlogged wood were often encountered on the same piece of timber. In seeking the most appropriate conservation method for this unusual material, its chemical characterization was considered necessary. This study examined the chemistry of the three dominant wood conditions found in the wreck. Fourier transform infrared spectroscopy and X-ray diffraction analysis were implemented in comparison to reference samples. Energy dispersive analysis was also used for assessing the inorganic composition of each condition. Moreover, for charred and semi-charred wood, proximate analysis was undertaken. Results obtained regarding the organic moieties of the waterlogged archaeological material, demonstrated that charred samples were chemically comparable to charcoals, semi-charred material showed similarity to thermally modified wood, whereas uncharred waterlogged wood was proven to have an analogous chemistry to biodeteriorated wood. Elemental analysis results also diversified among the three shipwreck's conditions. Sulfur, iron, and oxygen decreased in charred areas, whereas carbon increased. Proximate analysis showed that ash and fixed carbon content increased with charring, whereas volatile mater decreased. This work proved major chemical differences among shipwreck timbers' conditions owing to different degree of charring. These are anticipated to influence not only conservation methods' efficacy, but also the post-treatment behavior of the material. Further investigation is needed for correlating the chemistry of the archaeological material to its physical properties in order to contribute to practical aspects of conservation.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY 4.0)
Η παρούσα εργασία παρουσιάζει τις διαδικασίες συντήρησης που ακολουθήθηκαν για δεκαπέντε ένυδρα ξ... more Η παρούσα εργασία παρουσιάζει τις διαδικασίες συντήρησης που ακολουθήθηκαν για δεκαπέντε ένυδρα ξύλινα αντικείμενα που ανελκύστηκαν το 2013 από μεσαιωνικό ναυάγιο στον εμπορικό λιμένα της Ρόδου, στα πλαίσια του ερευνητικού έργου MERMAID. Η επιλογή των μεθόδων συντήρησης βασίστηκε στην κατάσταση διατήρησης των ευρημάτων, η οποία εκτιμήθηκε βάση της πυκνότητας του ξύλου και της αντίστασής του στη διάτρηση. Η μέθοδος που εφαρμόστηκε σε όλα τα αντικείμενα περιλάμβανε εμποτισμούς σε υδατικά διαλύματα πολυαιθυλενικής γλυκόλης, μοριακού βάρους 400 και 4.000 και ξήρανση με λυοφιλίωση. Οι συγκεντρώσεις των διαλυμάτων υπολογίστηκαν με το λογισμικό PEGcon. Τα αντικείμενα μετά την ολοκλήρωση των εμποτισμών ψύχθηκαν στους -20°C και ξηράνθηκαν στο σύστημα λυοφιλίωσης του Τμήματος ΣΑΕΤ. Μετά τη λυοφιλίωση τους, εγκλιματίστηκαν στους 21 °C και 65% RH. Όπου απαιτήθηκε συγκόλληση χρησιμοποιήθηκε κόλλα νιτρικής κυτταρίνης, η επιλογή της οποίας προέκυψε μετά από πειραματικό έλεγχο. Η μέθοδος της λυοφιλίωσης παρουσίασε άριστα αποτελέσματα όσον αφορά στη σταθεροποίηση του υλικού, στη διατήρηση των διαστάσεων αλλά και μορφολογικών του χαρακτηριστικών όπως η υφή και το χρώμα. Παρά ταύτα, η κατάσταση διατήρησης του κάθε αντικειμένου όπως και η τεχνολογία κατασκευής του, επηρέασε σημαντικά την συμπεριφορά του μετά την ξήρανση και καθόρισε τις εργασίες αποκατάστασης που ακολούθησαν. _________________________________________________________________________________________________________________________ This work presents the conservation process followed for fifteen waterlogged wooden artifacts found in a medieval shipwreck in 2013 at the port of Rhodes, Greece. Artifacts’ preservation state was determined based on their basic density and resistance to penetration. The conservation method applied involved a two-step- impregnation with PEG 400 and 4.000 followed by freeze drying. PEG concentrations were calculated with the PEGcon software. Objects after impregnation were frozen at -20°C and then freeze dried at 4x10-2 mbars. After freeze drying artifacts were conditioned at 21°C and 65% RH. For their reassembly a cellulose nitrate adhesive was used. Freeze drying gave excellent results as it preserved artifacts’ dimensions and wood’s physical properties such as color, grain and texture. Nevertheless, the preservation state of the objects and their manufacturing technology influenced greatly their post freeze drying behavior and defined the restoration and aesthetic reintegration procedures followed. _________________________________________________________________________________________________________________________ Full-text in Greek
Η ψηφιοποίηση διαδραματίζει σημαντικό ρόλο στην διαχείριση της ενάλιας πολιτιστικής κληρονομιάς κ... more Η ψηφιοποίηση διαδραματίζει σημαντικό ρόλο στην διαχείριση της ενάλιας πολιτιστικής κληρονομιάς και η εξέλιξη νέων ψηφιακών εργαλείων συμβάλλει στην ορθότερη και πιο ολοκληρωμένη αποτύπωση της. Επιπλέον, διευκολύνει την διαδικασία της τεκμηρίωσης, τόσο της κατάστασης διατήρησης όσο και των εργασιών συντήρησης. Λαμβάνοντας υπόψιν τις ανάγκες τεκμηρίωσης αλλά και τον όγκο του υλικού, ο οποίος συμπεριλαμβάνει ανελκυσθέντα ευρήματα και υλικό που παραμένει in situ, η ψηφιοποίηση τείνει να αποτελέσει μονόδρομο. Στόχος αυτού του άρθρου είναι να παρουσιάσει τις εφαρμογές της ψηφιακής τεχνολογίας στο πεδίο της συντήρησης ενάλιων αρχαιοτήτων, καθώς ακόμα δεν υπάρχουν πρωτόκολλα για την τυποποιημένη διαχείρισή του. Σε αυτό το πλαίσιο από το 2016 έχει γίνει μία συστηματική προσπάθεια δημιουργίας ενιαίου τρόπου διαχείρισης και ψηφιοποίησης της ενάλιας πολιτιστικής κληρονομιάς, χρησιμοποιώντας υπάρχοντα ψηφιακά εργαλεία. Αρχικά, δημιουργήθηκε ηλεκτρονικό δελτίο συντήρησης το οποίο εξελικτικά συνδέθηκε με βάση δεδομένων, μετατρέποντας σε αμιγώς ψηφιακή την τεκμηρίωση και διαχείριση του ανελκυσθέντος υλικού. Τα πλεονεκτήματα που πρόσφερε σε σύγκριση με την έντυπη μορφή των δελτίων είναι η προσβασιμότητα ανεξαρτήτως χρόνου και τόπου από όλους τους ενδιαφερόμενους, η δυνατότητα χαρτογράφηση και παρακολούθηση του υλικού από τον βυθό ως την αποθήκευση, ενώ παράλληλα οι απαραίτητες πληροφορίες προς τους μελετητές συγκεντρώνονται σε ένα σημείο. Επιπροσθέτως, η πρόσφατη δημιουργία επισκέψιμων ενάλιων αρχαιολογικών χώρων υπέδειξε την ανάγκη για την επίβλεψη του εκάστοτε χώρου. Από την σκοπιά της συντήρησης, κρίνεται απαραίτητη, σε συνδυασμό με τα μέτρα προστασίας, η συστηματική παρακολούθηση της κατάστασης διατήρησης των ναυαγίων μέσω καταγραφής τυχών φθορών. Αυτή πραγματοποιείται μέσω αποτύπωσης της κατάστασης διατήρησης κάθε αντικειμένου ξεχωριστά, βάση κριτηρίων που ορίστηκαν, σε σκαριφήματα που δημιουργούνται με σχεδιαστικό πρόγραμμα από φωτομωσαικά των ναυαγίων. Η συγκεκριμένη μέθοδος παρακολούθησης, αποτελεί μια πρωτότυπη εφαρμογή που δοκιμάστηκε πιλοτικά στο ναυάγιο της Περιστέρας Αλοννήσου, ενώ έχει αρχίσει και η προκαταρτική εφαρμογή του σε ναυάγια στους Φούρνους Ικαρίας. Το συγκεκριμένο εργαλείο προτείνεται για την μακροπρόθεσμη παρακολούθηση των ναυαγίων.
Condition reports of underwater finds should ideally include information
from the very moment the... more Condition reports of underwater finds should ideally include information from the very moment they are located on the seabed. In most cases, such information is nonexistent or mentioned separately in different field reports. The non-standardized methodology of condition reporting in an underwater archaeological survey or excavation and the limited number of underwater conservators are the main factors that such data is dispersed. This paper presents a condition reporting procedure focused on ceramic objects, the most common of archaeological finds in the Mediterranean basin. The aim is to record as much information as possible into one report, which will be a useful tool for all researchers. This report is displayed on an online multi-tab form with a database back-end, and contains information about the finds’ ID, burial conditions, preservation state, first aid treatment carried out in the field and the temporary laboratory, chemical and biological analysis, treatment after its transportation to the conservation laboratory, storage place and publications. It is also connected to a tablet-based GIS application, which shows the exact locations of the find from the sea bottom till storage. The online database provides access to updated information of the finds, anytime, anywhere; it gives the option to search for specific information and to provide the data in many different formats, as requested. This database relates information about conservation to the project, on a daily basis and for future reference.This condition reporting procedure, in connection with the database, was created within the framework of the Underwater Survey in Fournoi.
Conserving a charred medieval shipwreck: A preliminary study
In 2013, a medieval shipwreck, located at the port of Rhodes at a depth of 14 meters in a sandy b... more In 2013, a medieval shipwreck, located at the port of Rhodes at a depth of 14 meters in a sandy bottom, was partly excavated. The upper edges of its frames, parts of the outer planking and some stringers showed evidence of burning that was not uniform throughout the shipwreck. Core samples from seven different parts of the ship, showed a varied degree and depth of charring. Their moisture content, density and shrinkage values showed a great variation, indicating the diverse preservation state of shipwreck's timbers. The condition of the timbers, consisting of both charred wood with varied degrees of charring, and uncharred wood of different preservation states, creates a challenge for the ship's future conservation, as methods will have to deal with these different conditions, often encountered in the same piece of wood. This preliminary work studied comparatively three conservation methods, involved impregnation in aqueous solutions of different molecular weight Polyethylene Glycol (PEG), followed by air or freeze-drying. These included (i) PEG 400, (ii) PEG 4000 and (iii) a two-step impregnation system with PEG 400 and 4000. Methods were trialed on both charred and uncharred wood, and assessed for their efficacy based on wood's dimensional stability, using ASE% values, and on properties such as color and gloss. Samples used in conservation trials were representative of the shipwreck's complex condition. Prior to conservation, their physical properties were evaluated gravimetrically, their chemistry analyzed with Fourier Transform Infrared spectroscopy and their cellular morphology assessed with light and scanning electron microscopy to document condition. Results obtained from the conservation experiments demonstrated that charred and uncharred wood responded differently to impregnation, consolidation and drying regimes. However, each treatment had different advantages and disadvantages and thus practical dilemmas are posed for conservators treating simultaneously charred and uncharred wood without altering their color and gloss, so that the historical evidence of the fire will be preserved.
Conservation and Restoration in Underwater Antiquities Confrence, Zadar Croatia, 2019
The underwater environment creates a unique set of restrictions when it comes to lifting and hand... more The underwater environment creates a unique set of restrictions when it comes to lifting and handling objects. During the 2017 Underwater Archaeological Survey in Fourni, a cluster of finds consisting mainly of oil lamps was discovered concreted into the bedrock. It was decided the following year to lift these finds as one object, which presented the underwater conservation team with a series of problems that had to be tackled. The conservation procedure was divided in two different parts. The first part regarded the handling of these underwater as a whole, by documenting and estimating the preservation state, planning the extraction process and carrying out the lift. The second part regarded the handling of the concreted cluster of finds, when transferred to the temporary conservation laboratory, with the objects being gradually detached from the concretion one by one and documented once again as individual finds. What makes this case unique is that a large cluster of small fragile objects were handled together as one, whilst taking into consideration their individual needs as well as the requirements of it as a whole, since the concretion was in total 1m in length and 50 cm in width. Additionally, there was no sufficient information neither about the number of oil lamps inside the concretion or about their preservation state. The whole was detached in two big parts using the tools available and by taking into account the restrictions provided by the total length and weight of the concretion. Once secured with elastic bandages, they were lifted in baskets. At the temporary laboratory the oil lamps were detached carefully by using hand held rotary and pneumatic tools, whilst considering their extremely thin clay walls. Once separated, their individual conservation process begun. In total 22 lamps were retrieved and most of them underwent substantial cleaning considering the limited timeline of a survey. Most of them revealed figures of gods or otherwise on top and even the name of their workshop on the bottom, thus providing valuable information to the archeologists studying them.
In 2008, a late-12th-century merchant ship was discovered off the commercial port of Rhodes. The ... more In 2008, a late-12th-century merchant ship was discovered off the commercial port of Rhodes. The vessel caught fire before sinking and thus numerous hull timbers were found charred. Three main degrees of charring have been recorded that presented major chemical differences which indicated different conservation requirements. This study investigated the correlation between the chemistry of the waterlogged timbers and their physico-mechanical properties, to assist in the development of an appropriate conservation strategy. Scanning electron microscopy documented the morphology of charred, semi-charred and uncharred samples. Moisture content and density were measured gravimetrically, while porosity was evaluated using mercury intrusion porosimetry. Hardness was assessed using a modified Janka test and a penetrometer. The results obtained showed that differences in chemistry were highly correlated to the physico-mechanical properties of the timbers. The charred wood presented the lowest moisture content, shrinkage and porosity among the three charring conditions and it also had the highest density, Janka hardness and resistance to penetration. The exact reverse properties were recorded for the uncharred material, which was typical of badly preserved, waterlogged wood. The semi-charred wood presented transitional features. These results indicate that the uncharred wood is in need of consolidation, in contrast to the charred and semi-charred material, which may be left to air-dry untreated.
In 2008, a medieval wooden shipwreck was discovered at the port of Rhodes, Greece. The shipwreck ... more In 2008, a medieval wooden shipwreck was discovered at the port of Rhodes, Greece. The shipwreck was party burned, presenting a challenge for conservators, as uncharred, semi-charred and charred waterlogged wood were often encountered on the same piece of timber. In seeking the most appropriate conservation method for this unusual material, its chemical characterization was considered necessary. This study examined the chemistry of the three dominant wood conditions found in the wreck. Fourier transform infrared spectroscopy and X-ray diffraction analysis were implemented in comparison to reference samples. Energy dispersive analysis was also used for assessing the inorganic composition of each condition. Moreover, for charred and semi-charred wood, proximate analysis was undertaken. Results obtained regarding the organic moieties of the waterlogged archaeological material, demonstrated that charred samples were chemically comparable to charcoals, semi-charred material showed similarity to thermally modified wood, whereas uncharred waterlogged wood was proven to have an analogous chemistry to biodeteriorated wood. Elemental analysis results also diversified among the three shipwreck's conditions. Sulfur, iron, and oxygen decreased in charred areas, whereas carbon increased. Proximate analysis showed that ash and fixed carbon content increased with charring, whereas volatile mater decreased. This work proved major chemical differences among shipwreck timbers' conditions owing to different degree of charring. These are anticipated to influence not only conservation methods' efficacy, but also the post-treatment behavior of the material. Further investigation is needed for correlating the chemistry of the archaeological material to its physical properties in order to contribute to practical aspects of conservation.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY 4.0)
Η παρούσα εργασία παρουσιάζει τις διαδικασίες συντήρησης που ακολουθήθηκαν για δεκαπέντε ένυδρα ξ... more Η παρούσα εργασία παρουσιάζει τις διαδικασίες συντήρησης που ακολουθήθηκαν για δεκαπέντε ένυδρα ξύλινα αντικείμενα που ανελκύστηκαν το 2013 από μεσαιωνικό ναυάγιο στον εμπορικό λιμένα της Ρόδου, στα πλαίσια του ερευνητικού έργου MERMAID. Η επιλογή των μεθόδων συντήρησης βασίστηκε στην κατάσταση διατήρησης των ευρημάτων, η οποία εκτιμήθηκε βάση της πυκνότητας του ξύλου και της αντίστασής του στη διάτρηση. Η μέθοδος που εφαρμόστηκε σε όλα τα αντικείμενα περιλάμβανε εμποτισμούς σε υδατικά διαλύματα πολυαιθυλενικής γλυκόλης, μοριακού βάρους 400 και 4.000 και ξήρανση με λυοφιλίωση. Οι συγκεντρώσεις των διαλυμάτων υπολογίστηκαν με το λογισμικό PEGcon. Τα αντικείμενα μετά την ολοκλήρωση των εμποτισμών ψύχθηκαν στους -20°C και ξηράνθηκαν στο σύστημα λυοφιλίωσης του Τμήματος ΣΑΕΤ. Μετά τη λυοφιλίωση τους, εγκλιματίστηκαν στους 21 °C και 65% RH. Όπου απαιτήθηκε συγκόλληση χρησιμοποιήθηκε κόλλα νιτρικής κυτταρίνης, η επιλογή της οποίας προέκυψε μετά από πειραματικό έλεγχο. Η μέθοδος της λυοφιλίωσης παρουσίασε άριστα αποτελέσματα όσον αφορά στη σταθεροποίηση του υλικού, στη διατήρηση των διαστάσεων αλλά και μορφολογικών του χαρακτηριστικών όπως η υφή και το χρώμα. Παρά ταύτα, η κατάσταση διατήρησης του κάθε αντικειμένου όπως και η τεχνολογία κατασκευής του, επηρέασε σημαντικά την συμπεριφορά του μετά την ξήρανση και καθόρισε τις εργασίες αποκατάστασης που ακολούθησαν. _________________________________________________________________________________________________________________________ This work presents the conservation process followed for fifteen waterlogged wooden artifacts found in a medieval shipwreck in 2013 at the port of Rhodes, Greece. Artifacts’ preservation state was determined based on their basic density and resistance to penetration. The conservation method applied involved a two-step- impregnation with PEG 400 and 4.000 followed by freeze drying. PEG concentrations were calculated with the PEGcon software. Objects after impregnation were frozen at -20°C and then freeze dried at 4x10-2 mbars. After freeze drying artifacts were conditioned at 21°C and 65% RH. For their reassembly a cellulose nitrate adhesive was used. Freeze drying gave excellent results as it preserved artifacts’ dimensions and wood’s physical properties such as color, grain and texture. Nevertheless, the preservation state of the objects and their manufacturing technology influenced greatly their post freeze drying behavior and defined the restoration and aesthetic reintegration procedures followed. _________________________________________________________________________________________________________________________ Full-text in Greek
Η ψηφιοποίηση διαδραματίζει σημαντικό ρόλο στην διαχείριση της ενάλιας πολιτιστικής κληρονομιάς κ... more Η ψηφιοποίηση διαδραματίζει σημαντικό ρόλο στην διαχείριση της ενάλιας πολιτιστικής κληρονομιάς και η εξέλιξη νέων ψηφιακών εργαλείων συμβάλλει στην ορθότερη και πιο ολοκληρωμένη αποτύπωση της. Επιπλέον, διευκολύνει την διαδικασία της τεκμηρίωσης, τόσο της κατάστασης διατήρησης όσο και των εργασιών συντήρησης. Λαμβάνοντας υπόψιν τις ανάγκες τεκμηρίωσης αλλά και τον όγκο του υλικού, ο οποίος συμπεριλαμβάνει ανελκυσθέντα ευρήματα και υλικό που παραμένει in situ, η ψηφιοποίηση τείνει να αποτελέσει μονόδρομο. Στόχος αυτού του άρθρου είναι να παρουσιάσει τις εφαρμογές της ψηφιακής τεχνολογίας στο πεδίο της συντήρησης ενάλιων αρχαιοτήτων, καθώς ακόμα δεν υπάρχουν πρωτόκολλα για την τυποποιημένη διαχείρισή του. Σε αυτό το πλαίσιο από το 2016 έχει γίνει μία συστηματική προσπάθεια δημιουργίας ενιαίου τρόπου διαχείρισης και ψηφιοποίησης της ενάλιας πολιτιστικής κληρονομιάς, χρησιμοποιώντας υπάρχοντα ψηφιακά εργαλεία. Αρχικά, δημιουργήθηκε ηλεκτρονικό δελτίο συντήρησης το οποίο εξελικτικά συνδέθηκε με βάση δεδομένων, μετατρέποντας σε αμιγώς ψηφιακή την τεκμηρίωση και διαχείριση του ανελκυσθέντος υλικού. Τα πλεονεκτήματα που πρόσφερε σε σύγκριση με την έντυπη μορφή των δελτίων είναι η προσβασιμότητα ανεξαρτήτως χρόνου και τόπου από όλους τους ενδιαφερόμενους, η δυνατότητα χαρτογράφηση και παρακολούθηση του υλικού από τον βυθό ως την αποθήκευση, ενώ παράλληλα οι απαραίτητες πληροφορίες προς τους μελετητές συγκεντρώνονται σε ένα σημείο. Επιπροσθέτως, η πρόσφατη δημιουργία επισκέψιμων ενάλιων αρχαιολογικών χώρων υπέδειξε την ανάγκη για την επίβλεψη του εκάστοτε χώρου. Από την σκοπιά της συντήρησης, κρίνεται απαραίτητη, σε συνδυασμό με τα μέτρα προστασίας, η συστηματική παρακολούθηση της κατάστασης διατήρησης των ναυαγίων μέσω καταγραφής τυχών φθορών. Αυτή πραγματοποιείται μέσω αποτύπωσης της κατάστασης διατήρησης κάθε αντικειμένου ξεχωριστά, βάση κριτηρίων που ορίστηκαν, σε σκαριφήματα που δημιουργούνται με σχεδιαστικό πρόγραμμα από φωτομωσαικά των ναυαγίων. Η συγκεκριμένη μέθοδος παρακολούθησης, αποτελεί μια πρωτότυπη εφαρμογή που δοκιμάστηκε πιλοτικά στο ναυάγιο της Περιστέρας Αλοννήσου, ενώ έχει αρχίσει και η προκαταρτική εφαρμογή του σε ναυάγια στους Φούρνους Ικαρίας. Το συγκεκριμένο εργαλείο προτείνεται για την μακροπρόθεσμη παρακολούθηση των ναυαγίων.
Condition reports of underwater finds should ideally include information
from the very moment the... more Condition reports of underwater finds should ideally include information from the very moment they are located on the seabed. In most cases, such information is nonexistent or mentioned separately in different field reports. The non-standardized methodology of condition reporting in an underwater archaeological survey or excavation and the limited number of underwater conservators are the main factors that such data is dispersed. This paper presents a condition reporting procedure focused on ceramic objects, the most common of archaeological finds in the Mediterranean basin. The aim is to record as much information as possible into one report, which will be a useful tool for all researchers. This report is displayed on an online multi-tab form with a database back-end, and contains information about the finds’ ID, burial conditions, preservation state, first aid treatment carried out in the field and the temporary laboratory, chemical and biological analysis, treatment after its transportation to the conservation laboratory, storage place and publications. It is also connected to a tablet-based GIS application, which shows the exact locations of the find from the sea bottom till storage. The online database provides access to updated information of the finds, anytime, anywhere; it gives the option to search for specific information and to provide the data in many different formats, as requested. This database relates information about conservation to the project, on a daily basis and for future reference.This condition reporting procedure, in connection with the database, was created within the framework of the Underwater Survey in Fournoi.
Conserving a charred medieval shipwreck: A preliminary study
In 2013, a medieval shipwreck, located at the port of Rhodes at a depth of 14 meters in a sandy b... more In 2013, a medieval shipwreck, located at the port of Rhodes at a depth of 14 meters in a sandy bottom, was partly excavated. The upper edges of its frames, parts of the outer planking and some stringers showed evidence of burning that was not uniform throughout the shipwreck. Core samples from seven different parts of the ship, showed a varied degree and depth of charring. Their moisture content, density and shrinkage values showed a great variation, indicating the diverse preservation state of shipwreck's timbers. The condition of the timbers, consisting of both charred wood with varied degrees of charring, and uncharred wood of different preservation states, creates a challenge for the ship's future conservation, as methods will have to deal with these different conditions, often encountered in the same piece of wood. This preliminary work studied comparatively three conservation methods, involved impregnation in aqueous solutions of different molecular weight Polyethylene Glycol (PEG), followed by air or freeze-drying. These included (i) PEG 400, (ii) PEG 4000 and (iii) a two-step impregnation system with PEG 400 and 4000. Methods were trialed on both charred and uncharred wood, and assessed for their efficacy based on wood's dimensional stability, using ASE% values, and on properties such as color and gloss. Samples used in conservation trials were representative of the shipwreck's complex condition. Prior to conservation, their physical properties were evaluated gravimetrically, their chemistry analyzed with Fourier Transform Infrared spectroscopy and their cellular morphology assessed with light and scanning electron microscopy to document condition. Results obtained from the conservation experiments demonstrated that charred and uncharred wood responded differently to impregnation, consolidation and drying regimes. However, each treatment had different advantages and disadvantages and thus practical dilemmas are posed for conservators treating simultaneously charred and uncharred wood without altering their color and gloss, so that the historical evidence of the fire will be preserved.
Conservation and Restoration in Underwater Antiquities Confrence, Zadar Croatia, 2019
The underwater environment creates a unique set of restrictions when it comes to lifting and hand... more The underwater environment creates a unique set of restrictions when it comes to lifting and handling objects. During the 2017 Underwater Archaeological Survey in Fourni, a cluster of finds consisting mainly of oil lamps was discovered concreted into the bedrock. It was decided the following year to lift these finds as one object, which presented the underwater conservation team with a series of problems that had to be tackled. The conservation procedure was divided in two different parts. The first part regarded the handling of these underwater as a whole, by documenting and estimating the preservation state, planning the extraction process and carrying out the lift. The second part regarded the handling of the concreted cluster of finds, when transferred to the temporary conservation laboratory, with the objects being gradually detached from the concretion one by one and documented once again as individual finds. What makes this case unique is that a large cluster of small fragile objects were handled together as one, whilst taking into consideration their individual needs as well as the requirements of it as a whole, since the concretion was in total 1m in length and 50 cm in width. Additionally, there was no sufficient information neither about the number of oil lamps inside the concretion or about their preservation state. The whole was detached in two big parts using the tools available and by taking into account the restrictions provided by the total length and weight of the concretion. Once secured with elastic bandages, they were lifted in baskets. At the temporary laboratory the oil lamps were detached carefully by using hand held rotary and pneumatic tools, whilst considering their extremely thin clay walls. Once separated, their individual conservation process begun. In total 22 lamps were retrieved and most of them underwent substantial cleaning considering the limited timeline of a survey. Most of them revealed figures of gods or otherwise on top and even the name of their workshop on the bottom, thus providing valuable information to the archeologists studying them.
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This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY 4.0)
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This work presents the conservation process followed for fifteen waterlogged wooden artifacts found in a medieval shipwreck in 2013 at the port of Rhodes, Greece. Artifacts’ preservation state was determined based on their basic density and resistance to penetration. The conservation method applied involved a two-step- impregnation with PEG 400 and 4.000 followed by freeze drying. PEG concentrations were calculated with the PEGcon software. Objects after impregnation were frozen at -20°C and then freeze dried at 4x10-2 mbars. After freeze drying artifacts were conditioned at 21°C and 65% RH. For their reassembly a cellulose nitrate adhesive was used. Freeze drying gave excellent results as it preserved artifacts’ dimensions and wood’s physical properties such as color, grain and texture. Nevertheless, the preservation state of the objects and their manufacturing technology influenced greatly their post freeze drying behavior and defined the restoration and aesthetic reintegration procedures followed.
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Full-text in Greek
Conference Presentations by Eirini Mitsi
Επιπροσθέτως, η πρόσφατη δημιουργία επισκέψιμων ενάλιων αρχαιολογικών χώρων υπέδειξε την ανάγκη για την επίβλεψη του εκάστοτε χώρου. Από την σκοπιά της συντήρησης, κρίνεται απαραίτητη, σε συνδυασμό με τα μέτρα προστασίας, η συστηματική παρακολούθηση της κατάστασης διατήρησης των ναυαγίων μέσω καταγραφής τυχών φθορών. Αυτή πραγματοποιείται μέσω αποτύπωσης της κατάστασης διατήρησης κάθε αντικειμένου ξεχωριστά, βάση κριτηρίων που ορίστηκαν, σε σκαριφήματα που δημιουργούνται με σχεδιαστικό πρόγραμμα από φωτομωσαικά των ναυαγίων. Η συγκεκριμένη μέθοδος παρακολούθησης, αποτελεί μια πρωτότυπη εφαρμογή που δοκιμάστηκε πιλοτικά στο ναυάγιο της Περιστέρας Αλοννήσου, ενώ έχει αρχίσει και η προκαταρτική εφαρμογή του σε ναυάγια στους Φούρνους Ικαρίας. Το συγκεκριμένο εργαλείο προτείνεται για την μακροπρόθεσμη παρακολούθηση των ναυαγίων.
from the very moment they are located on the seabed. In
most cases, such information is nonexistent or mentioned separately
in different field reports. The non-standardized methodology
of condition reporting in an underwater archaeological survey or
excavation and the limited number of underwater conservators are
the main factors that such data is dispersed. This paper presents a
condition reporting procedure focused on ceramic objects, the most
common of archaeological finds in the Mediterranean basin. The
aim is to record as much information as possible into one report,
which will be a useful tool for all researchers. This report is displayed
on an online multi-tab form with a database back-end, and
contains information about the finds’ ID, burial conditions, preservation
state, first aid treatment carried out in the field and the temporary
laboratory, chemical and biological analysis, treatment after
its transportation to the conservation laboratory, storage place and
publications. It is also connected to a tablet-based GIS application,
which shows the exact locations of the find from the sea bottom till
storage. The online database provides access to updated information
of the finds, anytime, anywhere; it gives the option to search for specific
information and to provide the data in many different formats,
as requested. This database relates information about conservation
to the project, on a daily basis and for future reference.This
condition reporting procedure, in connection with the database, was
created within the framework of the Underwater Survey in Fournoi.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY 4.0)
_________________________________________________________________________________________________________________________
This work presents the conservation process followed for fifteen waterlogged wooden artifacts found in a medieval shipwreck in 2013 at the port of Rhodes, Greece. Artifacts’ preservation state was determined based on their basic density and resistance to penetration. The conservation method applied involved a two-step- impregnation with PEG 400 and 4.000 followed by freeze drying. PEG concentrations were calculated with the PEGcon software. Objects after impregnation were frozen at -20°C and then freeze dried at 4x10-2 mbars. After freeze drying artifacts were conditioned at 21°C and 65% RH. For their reassembly a cellulose nitrate adhesive was used. Freeze drying gave excellent results as it preserved artifacts’ dimensions and wood’s physical properties such as color, grain and texture. Nevertheless, the preservation state of the objects and their manufacturing technology influenced greatly their post freeze drying behavior and defined the restoration and aesthetic reintegration procedures followed.
_________________________________________________________________________________________________________________________
Full-text in Greek
Επιπροσθέτως, η πρόσφατη δημιουργία επισκέψιμων ενάλιων αρχαιολογικών χώρων υπέδειξε την ανάγκη για την επίβλεψη του εκάστοτε χώρου. Από την σκοπιά της συντήρησης, κρίνεται απαραίτητη, σε συνδυασμό με τα μέτρα προστασίας, η συστηματική παρακολούθηση της κατάστασης διατήρησης των ναυαγίων μέσω καταγραφής τυχών φθορών. Αυτή πραγματοποιείται μέσω αποτύπωσης της κατάστασης διατήρησης κάθε αντικειμένου ξεχωριστά, βάση κριτηρίων που ορίστηκαν, σε σκαριφήματα που δημιουργούνται με σχεδιαστικό πρόγραμμα από φωτομωσαικά των ναυαγίων. Η συγκεκριμένη μέθοδος παρακολούθησης, αποτελεί μια πρωτότυπη εφαρμογή που δοκιμάστηκε πιλοτικά στο ναυάγιο της Περιστέρας Αλοννήσου, ενώ έχει αρχίσει και η προκαταρτική εφαρμογή του σε ναυάγια στους Φούρνους Ικαρίας. Το συγκεκριμένο εργαλείο προτείνεται για την μακροπρόθεσμη παρακολούθηση των ναυαγίων.
from the very moment they are located on the seabed. In
most cases, such information is nonexistent or mentioned separately
in different field reports. The non-standardized methodology
of condition reporting in an underwater archaeological survey or
excavation and the limited number of underwater conservators are
the main factors that such data is dispersed. This paper presents a
condition reporting procedure focused on ceramic objects, the most
common of archaeological finds in the Mediterranean basin. The
aim is to record as much information as possible into one report,
which will be a useful tool for all researchers. This report is displayed
on an online multi-tab form with a database back-end, and
contains information about the finds’ ID, burial conditions, preservation
state, first aid treatment carried out in the field and the temporary
laboratory, chemical and biological analysis, treatment after
its transportation to the conservation laboratory, storage place and
publications. It is also connected to a tablet-based GIS application,
which shows the exact locations of the find from the sea bottom till
storage. The online database provides access to updated information
of the finds, anytime, anywhere; it gives the option to search for specific
information and to provide the data in many different formats,
as requested. This database relates information about conservation
to the project, on a daily basis and for future reference.This
condition reporting procedure, in connection with the database, was
created within the framework of the Underwater Survey in Fournoi.