Blombos Cave: Engraved Ochre and the Earliest Known Drawing

Blombos Cave is a small cave on the southern coast of South Africa where people lived during the Middle Stone Age, between about 100,000 and 70,000 years ago. Excavations since the 1990s have uncovered engraved pieces of red ochre, shell beads, a 100,000-year-old ochre paint workshop and, in 2018, the oldest known drawing, a cross-hatched pattern about 73,000 years old. These finds have made Blombos one of the most important sites for understanding how and when Homo sapiens began to think in symbols.

The site

Blombos Cave lies in a limestone cliff about 35 metres above the Indian Ocean, near the town of Still Bay in the Western Cape, roughly 300 kilometres east of Cape Town. The cave is small, with a floor area of only a few dozen square metres, but its layers are rich and well preserved.

The deposits fall into two broad parts. The upper part holds Later Stone Age material from the last 2,000 years or so. Below lies a deep sequence from the Middle Stone Age, divided by the excavators into phases known as M3 (the oldest, from about 100,000 years ago), M2 and M1 (about 75,000 to 72,000 years ago). Around 70,000 years ago a dune of wind-blown sand sealed the cave, preserving the older layers almost untouched until the late Holocene.

The ages of the layers come mainly from luminescence dating, which measures when buried sand grains were last exposed to sunlight, and from thermoluminescence dating of burnt stone. Specialists such as Zenobia Jacobs and Chantal Tribolo carried out much of this work.

Discovery and excavation

The archaeologist Christopher Henshilwood grew up in the region and knew the area from his youth. His early research focused on the Later Stone Age hunter-gatherers of the southern Cape, and in 1991 he began excavating the cave with that in mind, with regular field seasons from 1997. Digging below the recent layers revealed Middle Stone Age deposits of unexpected richness.

The first major publication, in 2001, described a set of 28 shaped bone tools from the Middle Stone Age layers, including awls and points. At the time, formal bone tools of this age were almost unknown, and the find signalled that Blombos would challenge established ideas.

Henshilwood’s team, which over the years included researchers from South Africa, Norway, France and elsewhere, excavated slowly and carefully, recording each find in three dimensions. Henshilwood later held posts at the University of Bergen in Norway and the University of the Witwatersrand in Johannesburg. Since 2017 the work has been part of SapienCE, a research centre on early Homo sapiens behaviour based in Bergen.

The engraved ochre

Ochre is a natural iron-rich earth pigment that ranges in colour from yellow to deep red. Thousands of pieces have been found at Blombos, many of them ground or scraped to produce powder.

In 2002 Henshilwood and colleagues reported in Science two pieces of red ochre from the M1 phase, about 75,000 years old, engraved with deliberate cross-hatched patterns. The larger piece, catalogued as SAM-AA 8938, carries a band of crossed lines framed by parallel lines on a ground facet. The authors argued that the pattern was a deliberately created design, not the by-product of scraping the stone for pigment.

Further study, published in 2009, identified more engraved pieces from several layers, including some from about 100,000 years ago. The repeated use of similar cross-hatched motifs over tens of thousands of years suggests a shared tradition rather than random scratches.

The French archaeologist Francesco d’Errico, a specialist in the microscopic study of engraved objects, worked with the team to examine how the lines were made. Studies of the grooves showed that they were cut with the pointed edge of a stone tool, often in several passes, and that the surfaces had been ground flat beforehand to prepare them for engraving.

Shell beads

In 2004 the team reported shell beads from the M1 phase, about 75,000 years old. They are shells of a tiny estuarine snail, Nassarius kraussianus, each pierced with a small hole. More than 60 have since been found.

Microscopic study shows wear around the holes and on the shells consistent with being strung and worn, perhaps rubbing against each other or against skin or clothing. Some carry traces of red ochre. Groups of beads found together often share similar size and wear, suggesting they came from the same strings. Similar beads from Taforalt in Morocco are about 82,000 years old, showing that people in both northern and southern Africa were making ornaments at around this time.

An ochre workshop 100,000 years ago

One of the most striking finds came from the oldest phase. In 2011 the team described two shells of the large sea snail Haliotis midae, a type of abalone, that had been used as containers for mixing an ochre-rich paste. Found in layers about 100,000 years old, the shells were accompanied by grindstones, hammerstones, bone and charcoal.

Analysis showed that the makers ground ochre to powder, mixed it with crushed, heated bone, charcoal and stone chips, and added a liquid to form a paint or paste. This is the oldest known evidence of a planned recipe for making a compound pigment. What it was used for, whether decoration, protection of the skin or another purpose, is unknown.

The oldest known drawing

In 2018 Henshilwood and colleagues published in Nature a find from the layers about 73,000 years old: a small flake of silcrete, a hard stone, measuring under 4 centimetres long. On one smooth face it bears six roughly parallel lines crossed by three curved lines, drawn in red ochre.

Experiments with ochre crayons and paint showed that the lines were drawn with a pointed piece of ochre rather than painted. The pattern ends abruptly at the edges of the flake, which suggests that it was originally part of a larger design on a bigger stone. The motif closely resembles the cross-hatching engraved on ochre pieces from the same site.

The flake is widely described as the oldest known drawing by humans. It is older than the earliest known figurative cave paintings, such as those of Sulawesi and much older than the famous cave art of Ice Age France and Spain.

Tools and daily life

The people of Blombos were skilled toolmakers. The M1 phase belongs to the Still Bay industry, known for thin, leaf-shaped bifacial points of silcrete and other stone. Some were finished by pressure flaking, a technique in which small flakes are pushed off with a pointed tool, which was previously thought to have appeared only around 20,000 years ago. The cave also produced shaped bone tools, including awls and points.

Food remains show a varied diet: shellfish, fish, seals, dolphins and land mammals such as eland. A few human teeth have also been found, consistent with Homo sapiens.

The debate over modern behaviour

For much of the twentieth century, many archaeologists believed that fully modern behaviour, including art, ornaments and complex tools, appeared suddenly in Europe around 40,000 years ago, in a “human revolution”. In 2000 Sally McBrearty and Alison Brooks challenged this view, arguing that such behaviours built up gradually in Africa over a much longer time.

Blombos became one of the strongest pieces of evidence for the African, gradual view. Together with sites such as Pinnacle Point and Sibudu, it showed that ochre use, ornaments and abstract designs were present in southern Africa long before the cave art of Europe.

Later finds elsewhere in southern Africa strengthened the picture. At Diepkloof Rock Shelter, about 60,000 years ago, people engraved ostrich eggshell water containers with repeated geometric patterns, showing that the habit of making abstract designs continued after the Blombos layers were sealed.

Some researchers remain cautious. They point out that the meaning of the patterns cannot be known, and that ochre and beads might have had practical or social uses that do not require complex symbolic language. Others note that such behaviours appear and disappear in the record rather than growing steadily. Despite these debates, Blombos is widely accepted as one of the clearest records of early symbolic behaviour.

Timeline

• c. 100,000 years ago: People at Blombos mix ochre paint in abalone shells (M3 phase).
• c. 100,000 to 75,000 years ago: Pieces of ochre are engraved with cross-hatched patterns.
• c. 75,000 years ago: Shell beads are made and worn; Still Bay points are produced (M1 phase).
• c. 73,000 years ago: A cross-hatched pattern is drawn in ochre on a silcrete flake.
• c. 70,000 years ago: Wind-blown sand seals the Middle Stone Age layers.
• 1991: Christopher Henshilwood makes the first excavation at the cave; regular fieldwork follows from 1997.
• 2002: The engraved ochre pieces are published in Science.
• 2004: The shell beads are published.
• 2011: The 100,000-year-old ochre workshop is described.
• 2018: The oldest known drawing is published in Nature.

Why it matters

Blombos Cave provides some of the clearest evidence that early Homo sapiens in Africa were creating abstract designs, wearing ornaments and preparing pigments by around 100,000 to 73,000 years ago. These finds pushed back the known origins of symbolic behaviour by tens of thousands of years and shifted the focus of research from Europe to Africa. The cave’s patterns and beads offer a rare glimpse into the minds of people who were, in many ways, much like us.