Mollusks Found in Building Materials Reveal Bronze Age Cretans Used Seagrasses to Make Their Bricks Fire-Resistant

A recent study led by Rena Veropoulidou (Museum of Byzantine Culture in Thessaloniki) and Maud Devolder (Ghent University) has uncovered an innovative technique for unraveling the mysteries of Bronze Age architecture in the Aegean region. Researchers have utilized remains of marine mollusks as indirect indicators to identify traces of disintegrated mud bricks used in constructions of that era.

Bronze Age architecture in the Aegean, especially in Crete, is characterized by its fragility. Many buildings used sun-dried mud bricks, materials that have almost completely disappeared over time due to environmental conditions. These structures, often supported on stone bases, have left minimal traces in archaeological sites, making it challenging to reconstruct their original design accurately.

However, this challenge has driven archaeologists to seek alternative methods to trace the presence of these materials. Among the most recent strategies is the use of mollusk remains, specifically those associated with marine plants such as Posidonia oceanica seagrass meadows. These plants, used as additives in brick-making, harbored small mollusks whose shells remained preserved in archaeological deposits.

The case study focused on Malia, a Minoan settlement in northern Crete. There, soil samples were collected from layers dating to the Early and Middle Bronze Age periods. These samples were carefully sieved and analyzed through flotation, a technique that separates light particles such as mollusk shells.

The analysis revealed a variety of mollusk taxa that exclusively inhabit Posidonia seagrass meadows. These findings were correlated with mud brick remains, suggesting that the mollusks were accidentally transported along with the marine plants used in construction. Evidence such as fragments of mud with Posidonia impressions supports the hypothesis that marine plants were not only used as a structural additive but also to enhance the thermal and mechanical properties of the bricks.

The research reveals that the use of these marine plants was intrinsically tied to the region’s architectural practices and natural environment. Posidonia meadows, common along Mediterranean coasts, provided an accessible and sustainable resource. Their incorporation into bricks offered fire resistance, thermal insulation, and greater durability against harsh weather conditions.

The settlement of Malia stands out as a natural laboratory for exploring these practices. From domestic structures to palatial buildings, mud bricks were an essential component of Minoan architecture. Through archaeomalacological analysis, researchers are not only reconstructing construction materials and techniques but also shedding light on the connections between the island’s inhabitants and their marine environment.

The use of mollusks as indirect indicators presents a revolutionary approach to studying perishable architectural materials. It also highlights the importance of adopting interdisciplinary methodologies in archaeology. The findings at Malia have broader implications for the study of other Mediterranean sites, where remains of marine plants and mollusks could reveal more secrets about past life and technologies.

However, the researchers caution that modern comparative studies are needed to better understand the associations between mollusks and their marine habitats. Additionally, the systematic implementation of sampling protocols in future excavations could significantly expand the archaeomalacological database, enabling more robust interpretations.