Workshop for Conservation of Roman Glass

The Project and the Course

General information  

Project type: Field school and conservation workshop. The various activities and team flexibility make this project suitable for both beginners and advanced students in conservation. Good manual dexterity and ability to perform delicate bench work are recommended.

The field school started: 2013 -2024. The workshop took place at the archaeological site of Stobi (R. of N. Macedonia); 

Venue: National Archaeological Reserve Deultum - Debelt

Artifacts & monuments in the project's focus: The glass objects for the workshop originate from the Roman and Late Roman necropoleis of Deultum (modern Debelt, Bulgaria). They are part of the collection of the National Archaeological Reserve Deultum - Debelt. 

Periods in the project's focus: Roman and Late Roman(1st – 6th century CE)

BHF partners in this project:  

• New Bulgarian University, Bulgaria;      
• National Archaeological Reserve Deultum - Debelt 

Workshop directors: Dr. Daniela Cherneva, Chief instructor, BHF Affiliate Conservator, PhD in Silicate Technology and Conservation;

Instructors & Lectures:  Biljana J. Peeva, Instructor, BHF Affiliate Conservator of Pottery and Glass. Artefacts conservator at National Institution Stobi (R. of N. Macedonia);

BHFS coordinator: Dr. Angela Pencheva

Field School Dates: June 06-20, 2026

Application Deadlines: May 06, 2026

Minimum length of stay: Two weeks.

Minimum age: 18 (16, if an adult family member accompanies the participant).

Number of field school places available: Maximum 10

Academic credits available: Participants can receive up to 6 European academic credits through New Bulgarian University.

Language: English

Experience required: No     

Visa Note: Citizens of the EU, EEA, UK, USA, Canada, Japan, Australia, and New Zealand do not need entry visas for Bulgaria. Those from countries not specified should check in advance if they require entry visas for either or both countries, and any associated costs will be the responsibility of the participants. 

Special requirements: Good physical condition and command of manual operations. All participants should bring clothes and toiletries suitable for hot and sunny weather, although the weather might sometimes be chilly and rainy. It is recommended that participants bring their laptops with at least 6 GB of free disk space and a mouse. Operating system recommended: Windows 10 or newer.

All participants are expected to prepare for the workshop by reading the recommended readings (the readings will be sent by e-mail to all registered students before the beginning of the project) as well as the additional readings.

The participants should inform the project staff about any health issues, allergies, and food preferences.

Participants will use the tools and equipment available at the site and are not expected to bring any additional equipment.

 Archaeological and Historical context

The National Archaeological Reserve “Deultum-Debelt” is located 17 km southwest of Burgas. Develton (Thracian: Debelton, "two-swamp area") was founded as an emporium of Apollonia Pontica in the 7th century BCE. From the 6th century to the 4th century BCE, the settlement served as an important trade center between Thracians and Greeks. It was annexed to the Roman Empire in 46 CE and became part of the province of Thrace. Emperor Vespasian established a colonia of the veterans from the VIII Augusta legion there. The city had an extensive territory, as attested by the inscriptions from Panchevo and Sladki Kladenci near Burgas. Between 130 and 150 CE, the city suffered serious damage from barbarian attacks. By the end of the 2nd century and the beginning of the 3rd century, Deultum had an area of approximately 62 acres (0.25 sq km) and there were temples dedicated to Asclepius and Cybele. A mint was active at Deultum from the reign of Emperor Caracalla to that of Philip the Arab. The city is mentioned in the Antonine Itinerary, composed in the early 3rd century. Deultum was sacked by the Goths in the second half of the 3rd century and was rebuilt shortly after, but on a smaller scale.

After the capital was moved from Rome to Constantinople in the 4^th century, Deultum became part of the defense system of the Roman Empire against the barbarian invasions, and a 5000 sq. m. fortification was built. During the medieval period, it was a border town between the Bulgarian Kingdom and the Byzantine Empire.

The rise of the sea level in the 13^th-14^th century led to moving the port east towards present-day Burgas. Deultum’s population steadily declined over the next 500 years until the ancient city and medieval fortress were completely abandoned.

The southern necropolis of Deultum was discovered in 2013 during construction in the area “Nedyalkovi kabi”. It is located on a hill on the southern shore of the Sredetska River. It was used during the Roman period – end of the 1^st century CE until the first half of the 3^rd century and later in the 9^th-10^th centuries. During the ongoing rescue excavations, archaeologists uncovered 518 grave structures (453 from the Roman period). Some of them had a rich grave inventory consisting of various ceramic and glass vessels, coins, tools, toiletries, as well as clothing elements. The glass vessels that will be conserved during the workshop come mostly from these graves.

   The Workshop

The Workshop for Conservation of Roman Glass will guide the participants through the history of ancient glass and the process of glass conservation, restoration, documentation, and study. Both the theoretical and practical courses will be based on Roman Glass from Deultum. The course includes three modules: 1) practical work in the conservation of replicas of Roman glass vessels and original items from the collection of National Archaeological Reserve Deultum; 2) lectures on topics related to the archaeological context of conserved vessels and conservation process of glass vessels; 3) excursions to the ancient coastal towns of Nessebar (UNESCO World Heritage Site) and Sozopol (including study visits to their archaeological museums). For more information, see the Course Program and Agenda below.

By the end of the workshop, the participants will:

• be familiar with the basic methods for conservation and documentation of ancient glass;
• develop basic/further practical skills (depending on the participant's initial level of qualification) in ancient glass conservation and documentation;
• deepen their knowledge of Mediterranean/European History and Archaeology through first-hand experience
• meet professionals who work in the areas of Classical Archaeology and Pottery & Glass Conservation
• contribute to the collection of the National Archaeological Reserve Deultum by conserving one or more authentic Roman vessels

All participants will receive:

• Project Readings;
• Balkan Heritage Field School Certificate specifying the topics and the hours of the field school activities (fieldwork, lectures, workshops, educational trips, etc.).   
• T-shirt.

The Team

Workshop instructors & lecturers:      

• Dr. Daniela Cherneva - chief instructor, Balkan Heritage Foundation Affiliate Conservator, (М.А. at Sofia Academy of Fine Arts - Specialty Conservation and Restoration, PhD in Silicate Technology and Conservation at University of Chemical Technology in Sofia, Postgraduate Specialization in Glass Restoration at RGZM (LEIZA today), Mainz, Germany);

• Biljana J. Peeva - instructor, (M.A. in Inorganic Technology and Environmental protection. Specialty Characterization of archaeological pottery), BHF Affiliate Conservator of Pottery and Glass Artefacts at National Institution Stobi (R. of N. Macedonia)

     

• Dr. Ralitsa Georgieva - lecturer, (PhD in Glass Technology at University of Chemical Technology in Sofia), Bulgarian Academy of Sciences;

     

• Angela Pencheva - BHF coordinator (PhD in Classical Archaeology); BHF Program Director

   

The Program

The glass conservation will provide a minimum of 120 hours of practical work, workshops/lab work, lectures/instructions, and guided tours:

Workshops and practical work:

• Conservation of Roman glass objects (with fragmented replicas of Roman vessels):
• Mechanical and chemical cleaning of selected original Roman and Late Roman glass shards
• Recording and documentation of glass shards and vessels
• Different methods for restoring glass objects, cleaning of extra resin and adhesive, mold making (using dental impression materials), application of the gap-filling resin, and refining the additions.        

Lectures:

• History of Pre-Roman and Roman glass technology. Core-formed glass vessels, mosaic glass; mold-formed vessels, glass blowing.
• Forms of natural silica, forms of natural glass. Chemical composition of glass.   

• Deterioration of archaeological glass, physical damage, and chemical deterioration.

• Introduction to preliminary glass analyses and condition assessment of the finds: observation under low and high magnification, sampling and samples, instrumental analyses.
• Basic techniques in ancient glass conservation: cleaning of glass and different methods for the treatment of glass artifacts. Materials used for cleaning, stabilization and conservation of ancient glass. Choosing consolidants and adhesives for archaeological glass, solubility, aging properties, reversibility, and working properties.
• Different methods for restoring glass artifacts, preliminary assembly, final assembly, application of resin, mold making, gap filling, and refining the additions. Materials used for the conservation and restoration of ancient glass.
• Roman Glass in Deultum - history and archaeological context.

• History and archaeology of Roman Deultum, the Western Black Sea Coast in Antiquity, the necropolis of the ancient town, the excavations, etc.

Guided Tours

• Guided visit of Sozopol: the Old Town Quarter and Archaeological Museum
• Guided visit of Nessebar: the Old Town Quarter and Archaeological Museum.   

Reading background   

Bray, Ch. Dictionary of Glass, Materials and Techniques (Pennsylvania Press, 2001)    

Chantal, Fontaine-Hodiamont.  Antique glass: Principles of conservation, displaying of conservation, displaying and maintenance, 2019

Cherneva, D. Archaeological glass from a mound in Pamuklia (Bulgaria),1^st -2^nd century AD: Identification, damage phenomena and conservation, Poster, 17th Triennial Conference ICOM-CC, 2014 Melbourne, Australia.   

Davison, S. Conservation and Restoration of Glass, (Oxford, 2006); 1-242.    

Grossmann,  R. A. Ancient Glass - A Guide to the Yale Collection 2002

Koob, S. P. Conservation and Care of Glass Objects (London, 2006).     

Lampropoulos V. et al. - Study of corrosion patterns and Conservation procedures of Roman glass vessels of 1st century AD, International Journal of Conservation Science 8 (1), 2007, 48-67.

Petrović M. Experience in the conservation and restoration of archaeological glass at the Archaeological Museum of Istria in Pula, Roman Pottery and glass manufactures, Archaeopress 2022, 362–366.

Perović Š. The Museum of Ancient Glass in Zadar (Croatia). In Proceedings of the 9th International Symposium on Archaeometry, 2015, 91-96, Institute of Archaeology, University of Zagreb.

Чуковска Л., Јанкуловска Пеева Б., Шијакова Т. Физичко-хемиски испитувања со примена на SEM-EDS и конзервација на пет стаклени садови од археолошкиот локалитет Стоби, Патримониум МК, година 16, брoj 21 / 2023.

(Physico-chemical Examinations Using SEM-EDS and Conservation of Five Glass Vessels From the Archaeological Site Stobi in R.n. Macedonia)

Travel, Accommodation & Practicalities

Travel

Project venue: National Archaeological Reserve Deultum - Debelt

 The nearest air terminals: Sofia Airport, Burgas Airport (45 km/28 mi), Varna Airport (160 km/100 mi). If participants arrive at one of these airports, a transfer to Debelt may be arranged by request. Transfers can be shared by several participants.

How to get there? Bus lines connect Debelt with Burgas and Sozopol.

A detailed travel info-sheet for reaching the site from the nearest international airport will be provided for enrolled students.

All students are individually responsible for arranging and covering the cost of their trip to the host country, including booking flights and obtaining any necessary travel documents or visas (if applicable). 

Visa Requirements: Citizens of the EU, EEA, UK, USA, Canada, Japan, Republic of Korea, Australia, and New Zealand do not need a visa to visit Bulgaria. Citizens of all other countries may need a visa. The Balkan Heritage Foundation can provide an official invitation letter to facilitate the visa application process at the relevant embassy. For further details, please visit our visa information page. Bulgaria is a full member of the Schengen Area and part of this borderless zone, allowing people to travel between Bulgaria and other Schengen countries without passport checks at land borders. Holders of a valid Schengen visa issued by another Schengen country can enter Bulgaria using that visa.

Accommodation & Meals

Accommodation: Accommodation will be at the archaeological base part of the National Archaeological Reserve - Deultum, which is located 22 km from Burgas. It has comfortable en-suite rooms with two to three beds and A/C. Free use of wifi, washing machine, and kitchen. Bed linen and towels are provided. 

Meals: 

Daily breakfast, lunch and dinner are covered by the reimbursement payment. Lunch and dinner are served in a nearby tavern. Food variety is represented by typical Balkan dishes combining fresh vegetables, dairy and meat. Vegetarian options are also available. 

Free Time & Trips

Free time:  Leisure activities during free time, such as swimming, sunbathing, walking, etc., can be facilitated by organizers.

Extra trips and excursions: BHFS participants could take advantage of their stay in the Balkans and take trips to some worth-seeing historical sites and towns nearby. BHFS encourages participants in the current project to visit after the field school:   

• The ancient city of Plovdiv is on the way to the Bulgarian capital Sofia,(the entire trip from Sozopol is about 370 km/ 230 mi)
• Istanbul, Turkey (340 km/ 215 mi from Sozopol).   

Technicalities & Practicalities

Insurance: The reimbursement payment does not cover medical costs. Participants must arrange their own insurance before their trip to Bulgaria. The insurance must cover, as a minimum, the following risks: medical treatment in case of an accident or disease,  as well as costs related to evacuation and repatriation.

Weather: A southern European (subtropical) climate dominates in the region, making summers hot (30-40° C/ 86-104° F) but breezy. Rainy and chilly days in this season are rare but not excluded.

What to bring?

• Participants are expected to bring clothing suitable to the workshop’s environment (both urban areas and countryside) and weather conditions ranging from hot and sunny to chilly and rainy. Light clothes and hats for sunny days, as well as raincoats for possible rainy and windy days, are recommended.    
• Comfortable shoes - visiting some of the sites requires walking on country roads and medieval cobblestone streets.     
• Wide-brim hat      
• White Lab coat
• A small backpack (for your water bottle, snacks, camera, etc.) 
• Swimming suit
• Medication - only prescription medication you may need. It is not necessary to bring non-prescription medication from your country since you can buy all basic non-prescription drugs in Bulgaria. Make sure to have all your medication in your carry-on luggage while traveling.
• A converter to the EU-type electricity wall plug, if needed.   
• EQUIPMENT: Participants are encouraged to bring their PC’s having at least 6 GB of free disk space, a mouse and a USB flash drive. Operating system recommended: Windows 10 or newer.    
• E-SIM or Data Roaming: We strongly recommend that participants purchase an e-SIM card with mobile internet tailored to their personal needs while in Bulgaria, unless they have coverage through their data roaming plan. While the hotels provide internet access, we cannot guarantee its quality or reliability, which may include interruptions, excessive network load, or potential server issues.
•  A good attitude for work, fun, study and adventures ;)

The Cost   

All field schools are organized as non-profit initiatives by the Balkan Heritage Foundation. The expenses related to participation in the field school, including costs incurred by participants, are financed through reimbursement payments made by the participants themselves.

BHFS project reimbursement payment includes coverage for: educational and fieldwork activities, accommodation and meals, tools and materials, access to project readings, issuance of a Certificate of Attendance, administrative costs, and travel related to fieldwork and excursions included in the program, along with relevant entrance fees.

BHFS project reimbursement payment does not cover: travel expenses to and from Sofia, nor any costs associated with activities not included in the field school program. Additionally, it does not include medical products and services or any expenses related to medical quarantine (such as food delivery or accommodation).

The costs in USD are approximate. Please check current exchange rates!

Early Bird Cost - until January 31, 2026:

Early Bird Cost for the two-week project session is 2799 EUR/ approx. 3200 USD

Regular Cost - after January 31, 2026:

The Regular Cost for the two-week project session is 2999 EUR / approx. 3500 USD

Reimbursement Transfer Options:

- Bank transfer
- Online transfers via the Balkan Heritage virtual POS Terminal. VISA, MASTERCARD & MAESTRO cards are accepted.      
-  Wise money transfer

For further information, contact the Admissions Office at: [email protected]!

 Discounts off the regular cost:

* 5% DISCOUNT OFF the regular cost available for:

1. Participation in more than one BHFS project in 2026 (discount applies to the second, third, etc. project).
2. Membership in the Archaeological Institute of America.

* 10% DISCOUNT OFF the regular cost available for:

1. Participation in any BHFS project/s in the past.

* 12% DISCOUNT OFF the regular cost available for:

1. Group Participation (three or more people who participate together in one BHFS project in 2026). The discount is valid for each participant.

* 15% DISCOUNT OFF the regular cost is available for:

1. Group Participation (three or more people, who participate in more than one BHFS project in 2026 (the discount is valid for each participant).
2. BHFS alumni who participate in more than one BHFS project in 2026 (discount applies to the second, third, etc. project).
3. BHFS alumni who attended a full project in the past and returned to the same project.

NOTE: 5% OF EVERY COST FOR THIS PROJECT DIRECTLY SUPPORTS THE BALKAN HERITAGE PROTECTION FUND'S ACTIVITIES!

For more information about scholarships, low-cost flights, hotels, etc., please feel free to contact us or look at our recommended links.

Academic Credits

New Bulgarian University grants 6 ECTS credit units for attending the field school. Transcripts of Records (ToR) are available upon request for an additional tuition fee of 400 EUR for EU students and 600 EUR for Non-EU students.    

Details: Regulations for Obtaining Transcripts of Records.    

Participants in the field school who do not need academic credit units are not expected to pay for them.