Study Analyzes Ancient Shipwreck Coatings to Uncover Naval Technologies
A collaborative study by researchers in France and Croatia has shed light on the organic waterproofing materials used on the Roman Republic shipwreck Ilovik-Paržine 1, which sank approximately 2,200 years ago near modern-day Croatia. Published in Frontiers in Materials, this research emphasizes the importance of waterproofing in ancient naval architecture, which has been largely overlooked until recently.
Dr. Armelle Charrié, an archaeometrist at the Laboratory of Mass Spectrometry of Interactions and Systems in Strasbourg, highlighted the significance of organic waterproofing materials in maritime history. “In archaeology, little attention is paid to organic waterproofing materials. Yet they are essential for navigation at sea or on rivers and are true witnesses of past naval technologies,” she said. The team identified two primary types of protective coatings on the ship: one made of pine tar, also known as pitch, and another comprised of a mixture of pine tar and beeswax.
Pine Tar and Beeswax Protect the Hull
The wreck was discovered in 2016 and has undergone several investigations since. This study represents the first instance of combining molecular and pollen analyses to discern the ship’s coatings and reconstruct the vegetation from which these materials originated.
The research was conducted in collaboration with the Department for Underwater Archaeology of the Croatian Conservation Institute and the ‘ADRIBOATS’ program at the Centre Camille Jullian of Aix-Marseille University in France. Charrié noted the region’s unique characteristics that influenced local shipbuilding traditions, saying, “Only studies like ours offer an overview of these traditions which bear witness to genuine know-how and diverse traditions.”
After analyzing ten samples of the coatings, the researchers employed molecular fingerprinting techniques to confirm the biological origins of the materials used. Findings revealed that all samples contained predominately heated coniferous resin or coniferous tar. Additionally, one sample revealed a combination of beeswax and tar, a mixture known as zopissa that enhances the flexibility of the adhesive and is easier to apply while hot.
Ancient Pollen Preserved in Sticky Pitch
The sticky nature of pitch allows it to capture and preserve pollen from surrounding vegetation for long durations. The analysis of this pollen enabled the researchers to identify the possible locations where the pitch was sourced or reapplied during repairs over time.
The pollen recovered from Ilovik-Paržine 1 indicated a diverse array of ecosystems. It included species from Mediterranean and Adriatic landscapes, such as forests rich in holly oak and pine, as well as matorral, a type of shrubland sponsoring olive and hazel trees. Additional pollen types contributed evidence of vegetation near riverbanks and coastal areas, suggesting a connection to the ship’s environment.
Evidence of Repeated Repairs Across the Adriatic
The analysis indicated that the ship received four to five distinct coating applications over its lifespan. Researchers observed that the stern and central sections were covered with a uniform material, while three unique batches were identified at the bow. This points towards a pattern of repeated repairs using materials sourced from different locations around the Mediterranean.
Previous studies suggested that the vessel was constructed in Brundisium, modern-day Brindisi, Italy. The new pollen evidence also suggests some coatings may have been applied there, while others were likely added near the northeast Adriatic coast, close to the wreck’s final resting place.
