The study area was not chosen at random. East Trenton sits in a neighborhood that the U.S. Environmental Protection Agency added to the Superfund National Priorities List in 2025, after investigators determined that soil across the area was contaminated with lead from 19th-century pottery manufacturing plants. Industrial legacies like this are common in older American cities, where factories that once fired glazed ceramics, smelted metals, or processed batteries left behind soils laced with lead that persists for generations. Because lead does not degrade, the contamination deposited more than a century ago remains chemically available at the ground surface today, where it can be picked up on shoes, clothing, pets’ paws, and wind-blown dust and carried directly into living spaces.

The scale of the outdoor contamination documented by the team is striking. Of 242 bare surface soil samples collected from residential properties, 86 percent exceeded the EPA’s residential soil lead hazard level of 200 parts per million, and nearly 94 percent exceeded screening levels designed to flag multiple pathways of lead exposure. Sean Stratton, a recent PhD graduate of the Rutgers School of Public Health and lead author of the study, emphasized that the sampling design made these numbers especially alarming: every sample came from bare soil at the surface, the fraction of the yard most likely to be contacted by children playing outside and most easily tracked indoors on footwear.

The indoor results are what elevate the study from a local soil survey to a finding with national implications. In the 42 homes where interior dust was sampled, 80 percent of floor dust samples exceeded the safety threshold, and this included homes with no interior lead-based paint whatsoever. Perhaps most telling, the researchers found no statistically significant difference in interior floor lead levels between homes with lead-based paint and homes without it. That symmetry points strongly to a shared external source. If paint were the dominant driver of indoor dust lead, homes free of lead paint should have shown markedly lower floor dust concentrations. Instead, the data suggest that outdoor soil, carried across the threshold by ordinary daily activity, is a likely cause of the indoor lead dust burden.

Technically, the investigation relied on a two-stage measurement strategy. Residents were recruited and trained to collect soil samples from 122 homes in the designated area, an approach that dramatically expanded the spatial coverage a conventional academic team could achieve. Researchers then used portable X-ray fluorescence analyzers, instruments that bombard a surface with X-rays and measure the characteristic fluorescent energies emitted by atoms in response, to determine lead-based paint levels on interior surfaces non-destructively. Finally, the team collected settled dust samples from floors, windowsills, and window wells in a subset of 42 homes, allowing them to compare paint lead loading, soil lead concentration, and indoor dust lead within the same properties. This combination of community-collected soil data and instrument-verified interior measurements gave the study both breadth and analytical rigor.

The health stakes could hardly be higher. According to the EPA, lead poisoning can impair brain development in young children, damage vital organs, and cause lasting behavioral and neurological harm. Young children are particularly vulnerable because they play close to the floor, engage in frequent hand-to-mouth activity, and absorb a larger fraction of ingested lead than adults do. A child crawling on a contaminated floor or digging in a contaminated yard can ingest lead dust that produces no immediate visible symptoms while quietly accumulating in developing bones and tissue. Public health agencies have long treated any elevated blood lead level in a child as preventable harm, which is why identifying non-paint sources of indoor exposure matters so much for intervention strategies.

Brian Buckley, director of research with the Rutgers Environmental and Occupational Health Sciences Institute and a co-author of the study, framed the finding as a correction to a widely held rule of thumb. The prevailing assumption, he noted, was that if lead appeared in household dust it must be coming from paint on the walls, and that a house built after 1978 was nothing to worry about. The East Trenton data show that this is not always true. The 1978 ban on consumer lead paint was a landmark public health achievement, but it addressed only one pathway of exposure. In neighborhoods with industrial soil contamination, the calendar age of a house offers little protection, because the hazard arrives from outside rather than from the walls themselves.

The study also stands out as a model of community-engaged environmental science, and that methodology is inseparable from its results. The Rutgers team built on a previous collaboration with the Newark Water Coalition, in which community scientists distributed 500 water testing kits to residents to evaluate whether flushing taps could reduce lead in drinking water. That earlier study, published this year in the Journal of Water & Health, found lead present across surveyed homes and showed that flushing did not eliminate the danger. Just as importantly, the experience established trust between the researchers and affected communities. Residents of East Trenton approached the team to ask for soil testing and granted access to residences that an outside research group might never have been able to enter. Stratton credited that Newark experience with demonstrating the power of citizen-led data collection and empowering residents to help characterize the environmental health threats in their own neighborhood.

The authorship itself reflects that partnership model. Alongside Rutgers researchers including Adrienne Ettinger, chief of staff for research at Rutgers Health, and Zorimar Rivera-Núñez, assistant professor at the Rutgers School of Public Health, the paper lists Shereyl Snider, community organizer for the East Trenton Collaborative, as a co-author. The East Trenton Collaborative, a community organizing and development initiative, works with organizations and public agencies including the New Jersey Department of Environmental Protection and the EPA. Embedding a community organizer in the author team is more than symbolic; it signals that the residents most exposed to the hazard helped generate, interpret, and publish the evidence about it. The research was funded by the National Institutes of Health through grants F31 ES035633, P30 ES05022, and S10 OD010713.

For homeowners, renters, and policymakers, the practical message is that lead risk assessments should look beyond paint. In cities with industrial histories, testing bare soil at the surface, covering exposed dirt with clean soil or mulch, enforcing shoe-removal habits at the door, and wet-cleaning floors and window wells can all reduce the transfer of contaminated particles into living areas, and remediation programs may need to target yards as aggressively as they target walls. For the scientific community, the East Trenton results add urban soil to the short list of exposure pathways that can single-handedly produce hazardous indoor dust. And for the residents of neighborhoods like East Trenton, the study provides something that has historically been denied to communities bearing the burden of industrial contamination: rigorous, peer-reviewed evidence, gathered in their own homes and backyards, documenting the hazard they suspected all along.

Subject of Research: Soil-derived lead contamination contributing to indoor household dust exposure in an urban community

Article Title: Contaminated soil poses hidden lead threat inside homes

Article References: Contaminated soil poses hidden lead threat inside homes. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: lead contamination, soil, indoor dust, community science, Superfund, East Trenton, public health, X-ray fluorescence, lead poisoning, EPA, environmental epidemiology, urban soil

The story begins in 79 C.E., when the eruption of Mount Vesuvius buried the Roman town of Herculaneum under volcanic ash, entombing a villa library that remains the only intact library known from antiquity. The pyroclastic heat carbonized more than a thousand papyrus scrolls, preserving them in theory but rendering them so brittle that early attempts to physically unroll them, beginning after their discovery in 1752, mostly produced heaps of ashes. Italian authorities eventually halted such efforts. Of the scrolls that were successfully opened, all proved to be texts unknown to scholars, many written by the Epicurean philosopher Philodemus, who lived in Herculaneum a century before the eruption. The surviving scrolls and fragments, roughly 1,800 in number, are now housed in Italy, France and England, and each one represents a book directly from Roman intellectual circles rather than a later medieval copy.

Douglas Seiler, an affiliate of Berkeley SETI and a retired professional who once worked in real estate, banking and invention, conceived the project after hearing about the scrolls while contributing to Panoseti, a new Berkeley telescope designed to search for laser signals from intelligent life in the galaxy. Seiler painstakingly sourced authentic papyrus and reed pens from Egypt and traditional lampblack ink from Japan, then hired high school students to inscribe the material with lines from Star Wars, the Bible and a quote from the 1960s science fiction television series The Outer Limits. He then rolled the papyrus into scrolls and carbonized them in his home laboratory by sealing them in a semi-sealed steel container with very little oxygen and heating it in a high-temperature furnace. The oxygen-poor environment replicated the charring of Vesuvius without reducing the material to dust, producing modern analogues of the ancient artifacts.

The central hypothesis was deceptively simple. Most ancient ink was made from soot, water and a binder such as gum Arabic, meaning that carbon ink sits on carbonized papyrus with almost no contrast in an X-ray image. But if the ink contained lead — a heavy metal that strongly absorbs X-rays — the letters should light up dramatically in a computed tomography scan. With collaborators including retired Berkeley chemists David Kreimer and Elena Kreimer, formerly manager of the College of Chemistry’s Microanalytical Facility, Seiler added calibrated amounts of lead nitrate to lampblack ink to create inks with different lead concentrations. Children of friends then wrote passages on fresh scrolls using traditional reed pens and the lead-spiked inks, and papyrologists Leah Packard-Grams and Jesse Obert of Berkeley’s Archaeological Research Facility scanned the scrolls to confirm the lead concentrations before carbonization.

To image the burned scrolls, Seiler enlisted Jake LaManna, a physicist at the Center for Neutron Research at NIST in Gaithersburg, Maryland, who created a three-dimensional X-ray CT scan of a charred scroll using the center’s laboratory X-ray source. LaManna jury-rigged a stand for the scroll and rotated it in the X-ray beam, recording thousands of slices that a computer assembled into a 3D rendering. Because lead absorbs up to 25 times more X-rays than the charred papyrus, the leaded ink stood out as bright spots against the darker paper, much like an overexposed region of a photographic negative. Ink with a lead concentration as low as 25 micrograms per square centimeter was easily detected. If you look at the images, Seiler said, the letters lit up like a Christmas tree.

A lucky coincidence accelerated the analysis. Michael Cyrus Daugherty, a postdoctoral fellow at NIST, had developed a program to digitally unroll the CT scans of the jelly-roll electrodes inside lithium-ion batteries. LaManna handed him the scroll data, and within a couple of days, after only minor modifications to account for the uneven and changing thickness of the papyrus along its length, Daugherty returned with examples of the scroll successfully unrolled in software. The demonstration showed that the same computational toolkit being applied to industrial imaging can be repurposed for the humanities, and that model scrolls offer a low-risk way to develop and refine unrolling algorithms without ever endangering the priceless originals.

The work builds directly on the ongoing Vesuvius Challenge, launched in 2023 by Brent Seales of the University of Kentucky together with venture capitalists, with a $700,000 Grand Prize offered to the first person to decipher four passages of at least 140 characters each from two Herculaneum scrolls scanned by X-ray CT. Within five months, two independent participants using artificial intelligence deciphered the first word, the Greek term for purple. In 2024, the same team used AI to read 15 full columns — less than a tenth of a scroll owned by the Institut de France — revealing an Epicurean philosophical treatise on perception and pleasure. In 2026, Seales’ team decoded the remains of scroll PHerc. 1667, nearly destroyed by earlier physical unrolling attempts, which appears to be a commentary on Stoic philosophy and may date from the second or third century B.C.E., possibly one of the oldest scrolls in the collection. All of these texts were extracted by virtually unrolling the scans and applying machine learning to detect extremely faint texture and morphological differences associated with carbon ink.

This is precisely where the new results could change everything. Lead-free carbon ink produces such a weak signal that most scrolls resist automated reading. Leaded ink, by contrast, produces a signature LaManna estimates is up to 25 times brighter than the surrounding papyrus. Critically, the researchers also demonstrated that an inexpensive handheld X-ray fluorescence scanner can detect leaded ink in a burned scroll, offering a simple screening method to identify which of the 1,800 surviving scrolls would be most amenable to X-ray CT decipherment. No one has systematically searched the Herculaneum collection for leaded ink, although at least one researcher previously found lead in the ink of a fragment left over from the early physical unrolling campaigns. Encouragingly, Packard-Grams used the same handheld technique on the Tebtunis papyri at UC Berkeley — fragments dating from 300 B.C.E. to 300 C.E. excavated in Egypt 126 years ago — and confirmed that some scrolls, generally those written after the first century C.E., contain lead or copper in their ink. If some Herculaneum papyri similarly contain lead, future CT scans can be tuned for sensitivity to that element, mapping the letters far more clearly as the scrolls are virtually unrolled.

The stakes, researchers argue, could hardly be higher. Almost everything from antiquity has been destroyed, and the Herculaneum scrolls are autograph books from the ancient world, frozen in time, rather than copies transmitted through Renaissance scribes. Packard-Grams, a Berkeley archaeology graduate student who consults as a papyrologist and now translates Greek and Egyptian writing in Berkeley’s Center for the Tebtunis Papyri, called the value of the project practically unquantifiable, describing the stakes as the largest in the history of Greek literature. She also hopes that ink chemistry, including any metals added deliberately or accidentally, could one day serve as a signature identifying the author of a specific text. Seiler, who funded the research and is first author of the paper alongside LaManna, Daugherty, David Kreimer, Michael McOsker of University College London and Jens Dopke of the Rutherford Appleton Laboratory, argues that a systematic lead analysis of the remaining papyri should begin now. His informal advisor, Berkeley nuclear engineering professor Karl van Bibber, observed that the gentleman scientist, often imagined as a figure of a bygone era, is alive and well in Berkeley. LaManna, for his part, wants to push further, studying ink composition beyond lead and building robust training datasets to strengthen the algorithms that will one day read the real scrolls. The model scrolls, Seiler noted, prove the concept: if there is lead in those ancient rolls, the letters will be there to see, and someone is going to read them.

Subject of Research: Virtual unrolling and X-ray tomography of carbonized papyrus scrolls from the Herculaneum library using lead-detectable inks and AI-based decipherment.

Article Title: To read 2,000-year-old burned papyrus scrolls, scientists make and burn their own

Article References: To read 2,000-year-old burned papyrus scrolls, scientists make and burn their own. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: Herculaneum scrolls, papyrus, Vesuvius, X-ray CT, lead ink, Vesuvius Challenge, papyrology, virtual unrolling, X-ray fluorescence, artificial intelligence, PLOS ONE, ancient texts

The Herculaneum papyri were discovered in the ruins of the town of Herculaneum, near Naples, Italy, and they represent one of the most extraordinary archives of ancient thought ever found. When Vesuvius erupted in 79 CE, the scrolls were covered by an estimated 65 to 70 feet of rock and ash. The extreme heat of the eruption carbonized the papyrus, transforming the delicate rolls into brittle, blackened cylinders that crumble at the slightest touch. While scholars have succeeded in opening and reading some of the scrolls, revealing previously unknown writings by Epicurus and other ancient thinkers, many more have proved simply too fragile to study by physical means. For centuries, the unopened scrolls have sat in collections as tantalizing, inaccessible objects.

In recent years, however, technology has begun to change the calculus. Artificial intelligence and X-ray tomography have allowed researchers to virtually unroll some of the scrolls and recover portions of their text without ever physically touching them. The technique involves scanning a scroll with X-rays in three dimensions and then using software to reconstruct and read the hidden writing layer by layer. Yet the method faces a fundamental physical obstacle: both the ink and the papyrus are made largely of the same material, carbon. Because the writing surface and the writing itself are chemically so similar, X-rays often have great difficulty distinguishing the letters from the background, and entire passages can remain effectively invisible even in the highest-resolution scans.

The turning point described in the new study comes from an unexpected discovery about the chemistry of the ancient ink itself. Some of the letters in fragments of the Herculaneum scrolls have been found to contain lead. Lead is a heavy metal that stands out vividly in X-ray imaging, and since X-rays can far more easily distinguish lead from papyrus than carbon from carbon, the presence of even small amounts of the metal could make text legible. The authors of the new paper therefore suggest a triage strategy: scan the surviving scrolls for lead first, and then attempt virtual unrolling on those scrolls that contain it, prioritizing the ones most likely to yield readable text.

Testing such an idea on the genuine Herculaneum scrolls themselves was not possible, since the irreplaceable artifacts cannot be subjected to experimental risks. Instead, the team did something remarkable: they recreated carbonized scrolls in the laboratory. The researchers wrote on new papyrus using ink prepared with various concentrations of lead, then heated the finished scrolls in a high temperature furnace until they carbonized. The result was a set of model scrolls that mimicked the tight packing of layers and the waviness of the ancient charred artifacts, replicating the very conditions that make unrolling algorithms struggle with the real thing.

The experiments delivered encouraging results on two fronts. First, X-ray fluorescence, a technique that maps the elemental composition of a sample, was able to detect lead in the recreated scrolls at each of the lead concentration levels the team tested. This means that even relatively modest amounts of lead in the ink should be detectable in a survey scan, validating the idea that lead detection could serve as a practical screening tool for the museum and library collections of unopened Herculaneum scrolls. A scroll that lights up with a lead signature would be flagged as a promising candidate for more intensive imaging.

Second, the team demonstrated that the text itself could be recovered. Using X-ray tomography combined with a custom software program, the researchers were able to re-read some of the words they had written on the carbonized model scrolls before charring them. In effect, the full pipeline from carbonization to detection to virtual unrolling to machine-assisted reading was exercised end to end. The reconstructed letters emerged from scans of a scroll that, to the naked eye, looked like an unremarkable blackened rod, precisely the form that has defeated conservators since the eighteenth century.

Beyond the immediate promise of reading more of the surviving scrolls, the laboratory-made artifacts serve a second, equally important purpose. Because the researchers know exactly what is written inside their recreated carbonized scrolls, they can use them as ground-truth training data for the algorithms that attempt to decipher real scrolls. Virtual unrolling depends on software that must infer the geometry of tightly packed, warped, and fused layers of papyrus, and that task becomes dramatically harder when the internal structure is unknown, as it is with the ancient originals. The model scrolls offer a rare test case in which the correct answer is already known, allowing developers to measure how well an algorithm performs and to refine it systematically. Success on the recreated scrolls, the team argues, could translate into improved success rates when the same algorithms are turned loose on the ancient texts.

The implications reach well beyond a single library. The Herculaneum papyri are the only intact library known to have survived from antiquity, and scholars believe many of the unopened scrolls may contain works by Epicurean philosophers, and possibly texts otherwise lost to history entirely. Every previously unknown book recovered from the collection has reshaped understanding of ancient philosophy, literature, and science. A reliable way to identify which scrolls are most likely to yield readable text could transform the pace of discovery, focusing expensive and time-consuming imaging campaigns on the artifacts with the highest probability of success. Douglas Seiler captured the spirit of the achievement in a characteristically understated remark: “It’s amazing what you can get electrons to do.”

The work, conducted with support from the Department of Commerce Radiation Physics Division and the Center for Neutron Research at NIST, demonstrates how physics, chemistry, and machine learning can converge on one of archaeology’s oldest unsolved problems. The recreated scrolls are published openly in PLOS One, and the freely available article provides full technical detail for other laboratories to build upon. For the curators who guard the carbonized library and for the scholars who have spent lifetimes waiting to read it, the message of the new study is straightforward: the combination of lead-sensitive X-ray fluorescence screening, tomographic imaging, and increasingly capable unrolling algorithms offers a realistic path into the interiors of scrolls that have kept their secrets since the afternoon the volcano buried them. The long-lost words of Herculaneum may not remain lost for much longer.

Subject of Research: Experimental recreation of carbonized Herculaneum papyrus scrolls to test lead-based X-ray imaging and virtual unrolling

Article Title: We may soon be able to read long-lost ancient scrolls damaged by eruption of Mt. Vesuvius

Article References: We may soon be able to read long-lost ancient scrolls damaged by eruption of Mt. Vesuvius. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: Herculaneum papyri, Mt. Vesuvius, carbonized scrolls, X-ray tomography, X-ray fluorescence, lead ink, virtual unrolling, machine learning, papyrus, PLOS One, ancient texts, Pompeii eruption

The research, led by Lena Merten and Felix Roosen-Runge of Lund University together with Gudrun Lotze of Malmö University and Marianne Ahmad, also of Malmö University, focused on yellow pea seeds, a crop of growing importance for sustainable food manufacturing. Peas are prized as a plant-based protein source, but the way their internal structure varies between species, cultivars, developmental stages and processing treatments remains poorly understood. Because seeds are multi-component biological materials, their characterization must stretch across length scales, from the arrangement of macromolecules to the architecture of cells. The team set out to build a workflow capable of spanning that entire hierarchy in a single, coherent analysis.

At the heart of the method is scanning Small- and Wide-Angle X-ray Scattering, or SWAXS, performed at the European Synchrotron Radiation Facility in Grenoble on beamline ID13. In a scanning experiment, a finely focused X-ray beam is stepped across the sample point by point. At each position, the scattered intensity records how molecules and nanostructures are organized locally: wide-angle patterns speak to packing at near-atomic distances, while small-angle patterns reveal features on the scale of tens to hundreds of nanometers. Rastered across an entire seed section, these measurements assemble into a map in which every pixel carries a full scattering fingerprint of its neighborhood, effectively turning the seed into a mosaic of nanoscale structural signatures.

Scattering alone, however, says nothing about which chemical elements reside where. To add that dimension, the researchers paired the scattering scan with X-ray fluorescence, or XRF, a technique in which the excited sample emits element-specific radiation. By recording fluorescence signals alongside the diffraction patterns, the team could overlay maps of elemental composition onto maps of molecular organization. This multi-modal integration is what elevates the approach: regions of the seed with similar scattering behavior can be compared against their elemental makeup, exposing relationships between structure and composition that neither measurement could reveal on its own.

The real bottleneck in such experiments is not data collection but data interpretation. A scanning SWAXS run on a seed produces thousands of scattering patterns, each a complex curve of intensity versus angle, and traditional analysis would require fitting each one with a predefined structural model. That approach is slow, subjective and biased toward structures the analyst already expects. The Swedish team instead implemented a fitting-free, data-driven segmentation workflow built on machine learning. Rather than asking what each pattern should look like, the algorithms group patterns by similarity, letting distinct structural domains emerge from the data itself.

This unsupervised strategy allowed the researchers to identify and characterize heterogeneous regions within the pea seeds and to classify structurally distinct domains without relying on predefined models. The payoff is quantitative comparability: because the classification is generated by the same data-driven procedure for every sample, domains can be compared systematically across different seeds, cultivars, developmental stages or processing conditions. A seed that has been stored for months, germinated, or exposed to industrial treatment can be mapped with the same yardstick, turning what was once a descriptive picture into a measurable, reproducible analysis.

The implications reach well beyond one legume. Seed structure underpins germination, aging, storage stability and the response of seeds to treatment during food processing, and structural variation is written into the genetic setup of each species and cultivar. A method that captures molecular organization, cellular architecture and elemental composition in one pass gives plant scientists a new lens on early growth stages and gives food scientists a way to connect processing steps to structural consequences. The authors emphasize that the approach is broadly applicable to other hierarchically organized biological materials, positioning it as a versatile tool for both plant science and plant-based food science.

Technically, the study demonstrates how synchrotron facilities and modern data science have become inseparable partners. Beamline ID13 provided the brilliant, focused X-rays needed to interrogate the seed at high spatial resolution, and the resulting datasets, recorded under a documented experimental DOI, were rich enough to sustain a fully data-driven analysis. The workflow sidesteps the model-fitting stage entirely, which not only accelerates analysis but also guards against circular reasoning, since the segmentation is derived from the measurements rather than from assumptions about what the seed contains. Combined with the complementary XRF channel, the pipeline delivers a layered portrait of the seed: where the elements are, how the molecules are arranged, and which structural territories dominate the tissue.

For the growing plant-based food industry, the timing is significant. As manufacturers reformulate products around pea protein and other legume ingredients, understanding how seed microstructure governs texture, nutrition and processing behavior becomes a competitive necessity. The multi-scale, multi-modal framework described by Merten and colleagues opens the possibility of screening varieties for desirable structural traits, monitoring how storage and treatment alter internal architecture, and ultimately breeding or engineering seeds whose structure is optimized from molecule to tissue. What was once invisible, the quiet hierarchy inside a humble pea, is now legible, pixel by pixel, pattern by pattern.

Subject of Research: Multi-scale structural and compositional analysis of yellow pea seeds using scanning SWAXS, X-ray fluorescence and machine learning segmentation

Article Title: Integrating scanning X-ray scattering and fluorescence for multi-scale analysis of seed structure supported by machine learning tools

Article References: Merten, L., Lotze, G., Ahmad, M., & Roosen-Runge, F. (2026). Integrating scanning X-ray scattering and fluorescence for multi-scale analysis of seed structure supported by machine learning tools. Plant Methods, 22(1), Article 78. https://doi.org/10.1186/s13007-026-01585-8

Image Credits: AI Generated

DOI: 10.1186/s13007-026-01585-8

Keywords: X-ray scattering, SWAXS, X-ray fluorescence, machine learning, pea seeds, plant science, food science, synchrotron, data-driven analysis, seed structure, hierarchical organization, Plant Methods

Utrecht occupies a special place in medieval Dutch ceramic history. The earliest evidence for pottery production there dates to the late 12th century CE, and by the 14th century the town had joined Haarlem, Leiden and Breda as a major manufacturing centre supplying both local markets and wider regional trade. Its products have been recovered as far afield as Alkmaar, Haarlem, Dordrecht and Amsterdam. The workshops themselves clustered in the suburbs of Bemuurde Weerd and Tolsteeg, north and south of the town walls, and along the banks of the Vecht river, where excavations have uncovered nine vertical updraft kilns with brick or clay floors, round or oval in plan and measuring up to five metres long.

The excavated waste heaps tell a story of technological transition. The first production phase at Zeedijk, dated 1150 to 1175 CE, yielded almost exclusively grey, round-based jars. After an apparent hiatus of roughly a century, the second phase, from 1275 to 1350 CE, saw a wider repertoire including lead-glazed reddish tripod forms, jugs, bowls and pans, though grey jars remained dominant. By the third phase, represented by the Oosterkade workshop (1350 to 1400 CE) and riverside workshops such as Anthoniedijk, Hogelanden and Lauwerecht (1375 to 1425 CE), lead-glazed redware had become far more prominent, and unglazed and lead-glazed floor tiles were also being produced.

To characterise the raw materials and firing technology, the team subjected the 59 samples, plus one clay sample from a waste pit at Bemuurde Weerd, to a battery of techniques: polarised light optical microscopy, wavelength-dispersive X-ray fluorescence spectrometry, X-ray diffraction and scanning electron microscopy with energy dispersive X-ray spectrometry. Thin-section petrography revealed two main fabric groups, a Coarse Group with large, moderately to poorly sorted quartz inclusions and a Fine Group with smaller, better-sorted inclusions. The size, rounded shape and bimodal distribution of the coarse quartz grains suggest they were deliberately added as temper, most likely derived from fluvial deposits, consistent with the Holocene river clays of the region.

The chemical data, measured on 26 major, minor and trace elements at the Fitch Laboratory of the British School at Athens, showed a strongly homogeneous, silico-aluminous dataset pointing to local clay sources. Principal component analysis identified three compositional groups, with a large, homogeneous group A accounting for more than 70 percent of the samples. All the Utrecht products were made from calcium-poor, iron-rich clay, with calcium contents below 2.5 percent, and the chemical similarity between the fired clay sample and the pottery, despite differences in calcium, may itself be evidence of quartz tempering. X-ray diffraction confirmed the mineral assemblage of quartz, illite-muscovite, K-feldspar and plagioclase, with redware bodies generally containing more hematite than greyware.

Firing temperatures emerged as consistently low. Most of the ceramics, 44 of them, were fired below 800 degrees Celsius, while a handful containing the high-temperature minerals gehlenite, diopside and mullite may have reached roughly 850 to 900 degrees or slightly above. The co-occurrence of surviving calcite and dolomite with these high-temperature phases implies short soaking times in the kiln. The glazes told their own story: single-layered, transparent coatings up to about 250 micrometres thick, of very high to high-lead type, with lead oxide contents between roughly 51 and 69 weight percent. Comparisons of corrected glaze and body compositions indicate that potters mixed lead oxide with silica before application, and that the yellowish-brown to greenish colour came from iron in the glaze over the reddish ceramic body.

The most novel element of the study was the application of small-angle neutron scattering, or SANS, to the question of how the vessels were formed. Measured non-destructively at the YS-SANS instrument of the Budapest Neutron Centre, 38 jar samples yielded data on the orientation and alignment of nanoscale domains in the ceramic fabric, which record the forces applied during forming. Thirty-two samples showed high isotropy values, indicating disorganised internal structures characteristic of percussion-building techniques such as pinching, moulding or tamper-and-concave-anvil forming. Combined with the wheel-made traces on rims and necks, this points to a two-stage strategy the authors call percussion-wheeling: the body formed by percussion, then the neck and rim refined on a rotational device.

Only six samples showed the low isotropy and significant tilting angles diagnostic of other techniques. One redware jar from the second phase at Zeedijk proved to be coil-built and wheel-shaped, while five jars, from both Zeedijk and Oudenoord, were genuinely wheel-thrown, three with clockwise and two with anticlockwise wheel rotation. Notably, all the wheel-thrown examples date to the second production phase after about 1275 CE, confirming a previously observed typo-technological shift from grey hand-formed jars to reddish tripod forms. Contrary to common expectations, the potters did not favour fine fabrics for wheel-throwing; nearly all the wheel-thrown jars were made from the coarse fabric. The persistence of percussion-wheeling across the 100-year hiatus between the first and second phases suggests a conservative, culturally embedded technological tradition, one perhaps also suited to producing the round-based jar shapes that were difficult to throw on a wheel.

The study also cautions against reading forming techniques from surface features alone. Interior depressions often interpreted as fingertip impressions from moulding appeared on wheel-thrown vessels too, and may instead reflect hands supporting the vessel wall during brushing, while interior ridges below the neck, sometimes taken as evidence of added coils, also occurred on wheel-thrown jars and may result from clay displacement during wheel work. The reasons for discarding the wasters were largely firing failures: warping and cracking from overfiring, loosened tripod legs and handles, and glazes accidentally fired in a reducing atmosphere. Taken together, the results portray a production tradition defined by both continuity and change, in which local potters favoured iron-rich, calcium-poor clay, tempered it with river sand, fired at low temperatures, and gradually adopted wheel-throwing and lead glazing, offering archaeologists a new quantitative template for reconstructing medieval craft knowledge and its transmission.

Subject of Research: The production technology and chaîne opératoire of medieval greyware and redware ceramics from 12th to 15th century Utrecht, the Netherlands

Article Title: Advancing the chaîne opératoire analysis of medieval greyware and redware ceramics: A case study from 12th to 15th centuries CE Utrecht, the Netherlands

Article References: Borgers, B., Gait, J., Bajnok, K., Allepuz, E. T., Bajnóczi, B., Len, A., & Griffioen, A. (2026). Advancing the chaîne opératoire analysis of medieval greyware and redware ceramics: A case study from 12th to 15th centuries CE Utrecht, the Netherlands. Archaeological and Anthropological Sciences, 18(9), Article 194. https://doi.org/10.1007/s12520-026-02554-x

Image Credits: AI Generated

DOI: 10.1007/s12520-026-02554-x

Keywords: medieval pottery, Utrecht, chaîne opératoire, ceramic technology, greyware, redware, small-angle neutron scattering, lead glazes, petrography, X-ray fluorescence, pottery workshops, the Netherlands