Flint tools, scorched soil and two pieces of spark-producing pyrite suggest humans were deliberately making fire in Britain 400,000 years ago — far earlier than firm evidence had previously shown

At a former clay pit in Suffolk, archaeologists found a small patch of ancient ground that had been heated repeatedly above 700°C. Heat-fractured flint handaxes lay nearby, along with two fragments of iron pyrite, a mineral that throws sparks when struck against flint.

Together, the finds provide what researchers describe as the earliest known evidence that humans could ignite fire for themselves. The buried surface at Barnham is about 400,000 years old, pushing firm archaeological evidence for fire-making back roughly 350,000 years.

The conclusion comes from a peer-reviewed study published in Nature. This is one study, not settled consensus. It does not show that fire-making was invented at Barnham, only that people there appear to have possessed the technology far earlier than the previous secure record.

A lakeside surface survived beneath the clay

Barnham’s archaeological deposits have been known for more than a century. The disused clay pit lies near the village of Barnham in Suffolk, about 140 kilometres north-east of London. Roughly 400,000 years ago, it was a spring-fed lake bordered by grassland and open woodland.

Animal remains record a very different eastern England. Elephants, deer, bison, beavers and macaque monkeys occupied the area. Humans visited the water’s edge and left stone tools in deposits dating to the Hoxnian Interglacial, a warm interval after a major glaciation.

Large excavations took place from 1989 to 1994, and researchers returned in 2013. Concentrations of reddened and cracked flint provided the first hints of burning. In 2019, the team exposed an isolated band of reddened clay on a buried land surface. The feature was only about half a metre across, close to the dimensions of a small campfire.

Establishing that it really was a hearth took four years. The researchers studied thin sections of sediment under a microscope, measured changes in magnetic minerals, used infrared spectroscopy and examined chemical products associated with combustion. The clay had experienced temperatures above 700°C, and several signals indicated repeated heating in the same confined place.

That combination helps rule out a passing wildfire. Natural fire can certainly scorch soil and damage objects, but repeated intense heating in one small patch is different. Flint handaxes found around the feature had also fractured under heat, linking the burning with a place where humans were making and using tools.

Controlling fire is not the same as making it

Archaeologists have identified much older sites where early humans probably used fire. Burned bones, stone artefacts and heated sediments in Africa and the Middle East extend back more than a million years, although individual sites remain debated.

Those traces cannot always answer the harder question of ignition. A group could gather burning branches after lightning or a grass fire, carry them to camp and maintain the flame. That would require planning and skill, but it would still leave people dependent on fire occurring naturally.

Finding a hearth at Barnham would therefore establish controlled fire without showing how it began. The two pyrite fragments change that interpretation.

Pyrite supplies the missing spark

Iron pyrite is often called fool’s gold because of its metallic yellow surface. When struck forcefully against a sharp piece of flint, small particles break away, oxidise and become hot sparks. With dry tinder and careful handling, those sparks can start a flame.

The Barnham pieces are small, each about two centimetres long. More important than their size is where they came from. Pyrite is not part of the site’s ordinary stone supply and is extremely rare in the surrounding region. The team reported that surveys of 26 sites classified about 121,000 stones without finding another fragment.

Its appearance beside a repeatedly heated surface and fire-damaged handaxes is consequently difficult to treat as a random geological coincidence. The simplest interpretation is that people obtained pyrite elsewhere, carried it to the lakeside and knew that it could help them make fire.

The case is still contextual. The researchers did not recover a complete fire-lighting kit frozen at the instant of use, and the two fragments alone would be ambiguous. Their force comes from the association of imported spark-producing mineral, concentrated burning and human-made flint tools.

In an independent Nature News and Views assessment, archaeologist Ségolène Vandevelde described the multiple techniques and contextual evidence as a convincing case for controlled fire that included deliberate ignition.

The fire-makers were probably early Neanderthals

No human bones were recovered from the Barnham hearth, so the identity of its users cannot be demonstrated directly. The researchers consider early Neanderthals the most likely candidates, based on human fossils of similar age from Swanscombe in southern England and Atapuerca in Spain.

That attribution needs restraint. Europe around 400,000 years ago contained populations whose relationships and names remain under discussion. As archaeologist Michelle Langley of Griffith University, who was not involved in the research, noted in an ABC Science report, several kinds of Homo complicate the identification.

The discovery also does not mean people in Britain invented fire-making. Before Barnham, the clearest physical evidence for producing sparks came from Neanderthal sites in northern France dating to about 50,000 years ago. The new site moves the surviving record back by around 350,000 years, but a first preserved example is not necessarily a technological beginning.

A technology that made fire available on demand

Reliable ignition would have changed the practical meaning of fire. A group no longer needed to wait for lightning or invest effort in keeping one flame alive indefinitely. People could choose a camp, produce heat when conditions demanded it and relight a hearth after moving.

Fire offered warmth and protection from predators. Cooking killed pathogens, softened food and made some nutrients easier to obtain. Light extended useful and social time beyond sunset. Those benefits are plausible, but Barnham cannot reveal exactly what was cooked, discussed or taught around this particular hearth.

Fire-making technology also required knowledge that reached beyond striking two stones together. People had to recognise pyrite, remember where it could be collected, transport it, prepare suitable tinder and coordinate a sequence of actions. The mineral’s rarity at Barnham makes that chain of knowledge central to the find.

Why two stones can rewrite such a long timeline

Evidence for ancient fire-making is unusually difficult to preserve. Ash can blow away, charcoal can decay or wash from a site, and heated sediment can erode. Wildfires produce some of the same traces as hearths. Even pyrite weathers readily, which may help explain why it is seldom recovered from very old sites.

Barnham happened to preserve the necessary pieces together. Pond-side sediments sealed the scorched surface, flint survived the heat and two fragments of a vulnerable spark-making mineral remained close enough to be recognised as part of the same archaeological setting.

Langley cautioned that this is the oldest evidence found so far, not a likely record of the first successful attempt. If fire-making appears at one site under exceptionally favourable preservation conditions, other populations may already have been using it without leaving evidence archaeologists can identify.

The important change is therefore evidential. Humans had been associated with fire for far longer, but Barnham provides a rare answer to how a flame could have begun. A small patch of baked earth, broken flint and two pieces of imported pyrite place deliberate fire-making deep inside the Middle Pleistocene.