Restoration of Marble Statues from Heraclea Sintica with CaLoSil® and Carbon Anchors

Description

Dear friends, it was a privilege for us to take part - albeit indirectly - in the project for the display of two ancient statues discovered during the 2024 archaeological season. The finds were unearthed as part of large-scale excavations led by Prof. Vagalinski in the ancient city of Heraclea Sintica.

The first statue is known to represent Lucius Caesar, grandson of Augustus, while the second is an imperial figure from the time of Marcus Aurelius, whose identity remains unknown. The statues were restored by conservation specialists Dr. Kitan Kitanov and Reneta Karamanova-Zlatkova from the team at the National Institute of Archaeology with Museum at the Bulgarian Academy of Sciences (NAIM-BAS). They were later exhibited to the public in the Regional History Museum in Petrich and the National Archaeological Museum in Sofia, respectively.

As part of our commitment to the conservation of historical monuments and artifacts, and as suppliers of specialized materials, we were fortunate to contribute products suitable for the restoration of these valuable statues.

The Statue of Lucius Caesar - Grandson of Augustus, Depicted as Hermes

For structural consolidation and deep strengthening of the statue of Lucius Caesar, we provided CaLoSil^® IP25 - a high-tech nano-based system of colloidal calcium hydroxide designed for the conservation of stone artifacts. The product penetrates the material, stabilizing weakened zones without affecting vapor permeability or leaving visible traces. Cleaning was done using gentle methods, including ultrasonic treatment instead of aggressive chemicals.

Today, this restored sculpture is part of the permanent exhibition at the Regional History Museum - Petrich.

Lucius Caesar statue during restoration by Dr. Kitan Kitanov

The statue of Lucius Caesar during restoration by Dr. Kitan Kitanov. Source: https://www.facebook.com/PetrichHistoryMuseum

CaLoSil IP25 used for marble statue consolidation

Restoration process of Lucius Caesar statue

Gentle cleaning of marble statue using CaLoSil IP25

Lucius Caesar statue before and after restoration

Source: https://www.facebook.com/PetrichHistoryMuseum

Unidentified Imperial Figure from the Time of Marcus Aurelius

The second statue, also found in the Great Canal during the 2024 season, has been stylistically dated to the reign of Emperor Marcus Aurelius (2nd century AD). Although still not definitively identified, its scale and context suggest a high-ranking figure from the imperial family.

During the restoration, serious damage (cracks) was discovered in the marble structure. To ensure safe reinforcement and vertical stability, carbon fiber rods (carbon anchors) were used - ARMOSHIELD BC - a solution that offers reliable structural stability with minimal visual impact. CaLoSil^® IP25 was also used for consolidation.

The statue was first exhibited at the National Archaeological Museum in Sofia and will be transferred to the Petrich museum to be displayed next to the first statue.

Restoration process in National Archaeological Museum

Head of statue from Heraclea Sintica found separately

Missing head being mounted on statue from Heraclea Sintica

Cracks in the marble structure of the statue

Statue before restoration by Reneta Karamanova-Zlatkova

Restored statue with ARMOSHIELD BC and CaLoSil IP25

The statue of the unidentified imperial figure before and after restoration by Reneta Karamanova-Zlatkova.

Source: https://www.facebook.com/PetrichHistoryMuseum

Products and Technologies

Projects of this caliber require not only expertise but also precisely selected materials with proven effectiveness. As the saying goes, we had the chance to be in the right place at the right time - and with the right products, namely:

CaLoSil^® IP25, preferred by leading European institutions for stone conservation;
Carbon fiber rods for structural reinforcement ARMOSHIELD BC, chosen for their compatibility with historical materials and reversibility;
We provided technical and logistical support and consultations to the restoration team for product selection and application.

We would also like to express our sincere thanks to Prof. Gerald Ziegenbalg, our long-time partner, whose company IBZ-Salzchemie GmbH manufactures the restoration systems CaLoSil, CaSoPal, CaLoXil and SioXaL. He supported the project, behind the scenes, with laboratory analyses and expert evaluations.

For us, this was not just another project - it was a modest but meaningful contribution to the preservation of Bulgarian and global cultural heritage, to the future of science, and to the meeting of generations with history carved in stone.