During my traineeship as a restorer at the former Rheinisches Landesmuseum Bonn (today: LVR State Museum Bonn) got ich the wonderful and for me very exciting commission to subject a late Roman glass with graver engraving from the 4th century AD to a comprehensive restoration.
I got the glass in individual fragments in the original condition from an excavation in the Cologne/Bonn area.
According to the general practice for such a restoration at the time, the color of the missing areas should be reproduced true to the original, thus restoring the original shape of the glass.
I made all the missing pieces of glass out of a suitably colored resin to complement the original shards.
Today the restored glass is an integral part of the permanent exhibition at the LVR LandesMuseum in Bonn. I'm particularly proud of that.
On the Restoration of Roman Glass Objects
Restoring Roman glass is a fascinating process that requires both technical expertise and a deep understanding of ancient history and culture. Often preserved in the form of vessels, window elements or jewelry, Roman glass offers unique insights into the technical skills and aesthetic preferences of Roman civilization. As glass is a fragile material that has survived for centuries in tombs, settlements or wrecks, many pieces are severely damaged, broken or marked by corrosion. Restoration aims to preserve these objects, restore their original form and tell their story without distorting their archaeological and material value.
The first step in restoring Roman glass is to carefully analyze the object. Experts first examine the condition of the glass to assess its composition, state of preservation and possible damage. Roman glass was usually made from a mixture of sand, soda and lime and can develop layers of corrosion over time due to chemical processes in the earth. These often iridescent layers, which are created by the interaction of the glass with moisture and chemical substances, are aesthetically fascinating on the one hand, but can also endanger the stability of the object. Scientific investigation methods such as X-ray fluorescence analysis or scanning electron microscopy help to determine the chemical composition and degree of damage more precisely.
After the analysis, the glass is cleaned, a particularly delicate process because the aim is to remove dirt and deposits without damaging the surface. Often the layers of corrosion are unevenly distributed and firmly bonded to the glass. Conservators therefore use finely tuned techniques such as mechanical cleaning with microscale arrows, the removal of deposits under the microscope or chemical baths containing precisely dosed substances. It is crucial that no irreversible damage occurs and that the original substance of the glass is preserved as completely as possible.
An important aspect of Roman glass restoration is the reconstruction of broken or incomplete pieces. Since many glass objects are found in a fragmented state, restorers often have to put these fragments together like a three-dimensional puzzle. To ensure stability, they use special adhesives that are transparent and reversible. One of the biggest challenges is replacing or adding to missing parts of the glass. This involves using modern materials such as synthetic resin, which is colored and shaped to blend harmoniously with the original object without distorting the authentic substance. Many restorers deliberately choose to leave additions visible in order to make the line between original and reconstruction clear and to maintain scientific standards.
Another important step in the restoration of Roman glass is the stabilization of the material. Particularly in the case of heavily corroded or porous glass objects, it may be necessary to treat the glass with consolidating agents that penetrate the structure and strengthen it. This treatment is often combined with the creation of an optimal storage and display environment to protect the restored object from further damage. Glass is particularly sensitive to fluctuations in temperature and humidity, which is why constant conditions are essential in museums and collections.
However, the restoration of Roman glass goes beyond purely technical restoration. It also serves to make the history of the object and its cultural context visible. Many glass objects that come from Roman tombs, villas or trading places tell stories about the trade routes, the social status of their owners or the technical development of glassmaking. Restoration makes it possible to better understand and communicate these stories. By reconstructing the form and function of an object, scientists and visitors can gain insights into life in Roman antiquity, whether through the elegant shape of a perfume bottle that indicates the importance of cosmetics or through a simple drinking vessel that reflects people's everyday lives.
Another aspect of the restoration of Roman glass is the ethical use of the material. Conservators must always consider how far they can intervene in the process of reconstruction without endangering the integrity of the object. The balance between preservation and aesthetics is a central theme in modern restoration practice. Many conservators today follow a "minimal intervention" approach, which aims to change the original substance as little as possible and to respect the traces of time as part of the object's history. At the same time, there are cases in which a complete reconstruction is necessary in order to make an object recognizable or stable for display.
In addition to traditional methods, the restoration of Roman glass has benefited from technological advances in recent years. Digital techniques such as 3D scanning and modeling make it possible to virtually reconstruct fragments or add missing parts without touching the original. This opens up new ways to visualize and analyze damaged or fragmented objects. 3D printing is also increasingly being used to produce exact replicas of Roman glass that can be used in exhibitions or for educational purposes.
The restoration of Roman glass is thus a multidisciplinary process that combines art, science and history. It requires not only craftsmanship and technical knowledge, but also a deep understanding of the cultural and historical dimensions of the objects. Through restoration, the fragile heritage of Roman antiquity is preserved and made accessible to a wider audience. At the same time, it raises fundamental questions about the treatment of cultural artefacts and shows how modern technologies and methods can help keep the past alive. Roman glass is not only a testament to the Romans' craftsmanship and aesthetic mastery, but also a medium that invites us to reflect on the fragility and value of our cultural heritage.