Interior of the Pantheon, Rome. (Francesco Riccardo Iacomino/Moment/Getty Images)
The Roman Empire helped transform humanity for centuries during its reign, then left a legacy that has continued to influence civilization ever since.Even the ancient Romans had to stand on giants' shoulders, though.That includes not just earlier civilizations like Egypt and Greece, but also countless prehistoric people whose innovations have been largely lost to history – or, in some cases, erroneously attributed to later generations.In a new study, researchers report that a sophisticated plaster-making technique long credited to the Romans was also used by Neolithic people about 8,000 years earlier.But how is that possible?Ancient Rome is renowned for its engineering prowess, as seen in iconic projects like the aqueducts and the Pantheon. In addition to their design and construction skills, Roman builders likely benefitted from durable concrete and other high-quality materials.Some Roman buildings incorporated dolomite-based plaster, a quick-drying paste, which is stronger and more water-resistant than the traditional calcitic plasters often produced in antiquity."However, using dolomitic lime is challenging and requires a high level of expertise at all steps of preparation, which may explain why it is not commonly found in archaeological sites," the researchers write.Dolomite refers to a mineral made of calcium magnesium carbonate, or to a rock featuring mostly this mineral. Similar to calcitic limestone, it can serve as a source of the inorganic material lime, which in turn can be useful in the production of certain building materials.The earliest written record of dolomitic lime seems to come from the Roman architect and engineer Vitruvius during the first century BCE, the authors note.While Vitruvius didn't mention dolomite by name, he seemed to describe the mineral in a discussion of lime production.Plaster had been common for a long time before Vitruvius, but there is little indication of anyone using dolomitic lime before his description of it about 2,000 years ago.Archaeological evidence suggests the main materials for making plaster in prehistory were calcite and gypsum.About 10,000 years ago, however, people at a Neolithic settlement in the Judean Hills apparently made dolomite-based plaster, leaving behind subtle clues that went unnoticed until now, the researchers report.Located in what's now Israel and Palestine, this region was already a hub of human activity at the time, bustling with settlements thousands of years before the dawn of the Iron Age or the Roman Empire.An overview of the Motza archaeological site. (Maor et al., J. Archaeol. Sci., 2026)One of those settlements eventually became the modern-day archaeological site known as Motza, located about 5 kilometers west of Jerusalem, where researchers conducted a series of excavations between 2015 and 2021 before construction of a highway through the area.Sifting through multiple occupations over the millennia, the researchers focused on a large Neolithic settlement dated to roughly 9,000 years ago. They found more than 100 plaster floors from that era, noting many were "particularly well-preserved and coated with red pigment".They also found separate kilns where residents had burned either limestone or dolomite to make plaster, indicating a degree of sophistication not often attributed to Neolithic people.Calcitic and dolomitic lime require different conditions for plaster production, the researchers explain, and yet these prehistoric people evidently understood that well enough to build specialized kilns for each substance.Using dolomite to make plaster was an impressive feat for humans at the time, but the method employed at Motza remains intriguing even by modern standards, the researchers add."They may have successfully made dolomitic plaster where dolomite is fully recrystallized along with the calcite, something that to our knowledge has not been observed anywhere else and was thought to be physically impossible," they write.Related: We Finally Know Why Ancient Roman Concrete Stood The Test of TimeAside from capitalizing on a local abundance of dolomite, this method likely yielded a superior plaster for use in buildings, with greater strength and water resistance than traditional alternatives.Given the difficulty of making dolomite-based plaster, plus the lack of earlier evidence, credit for its invention has long fallen to Ancient Rome.While it's possible the technique survived for 8,000 years after Motza and then resurfaced in Rome, the lack of archaeological evidence from the interim seems to indicate the Romans independently discovered it."The results suggest a technology lost to history," the researchers write.The study was published in the Journal of Archaeological Science.
