The world’s oldest drawing might be easy for a casual observer to miss: a 38.6mm (1.52 inch) long flake of silcrete (a fine-grained cement of sand and gravel) with a few faint reddish lines drawn on one smooth, curved face using an iron-rich pigment called ocher. The lines would have been bolder and brighter when the drawing was new, according to University of Bergen archaeologist Christopher Henshilwood and his colleagues, but over time they’ve lost pigment to rinsing and wear, leaving them faint and patchy. But an archaeologist working at Blombos Cave, about 300km (186 miles) east of Cape Town, South Africa, noticed the markings while analyzing stone flakes and debris excavated from a 73,000-year-old layer of the site.
The design features six nearly parallel lines, with three curved lines cutting across them at an oblique angle, but it hints at a more complex piece of work. All the lines cut off abruptly at the edges of the flake, which suggests that the pattern archaeologists see today is just a fragment of something originally drawn on a larger surface and later broken.
“The pattern was probably more complex and structured in its entirety than in this truncated form,” wrote Henshilwood and his colleague. Modern viewers will likely never know what the rest of the drawing looked like—or what it meant to people 73,000 years ago.
You’re never too old for crayons
Even if we can’t grasp the prehistoric artist’s meaning, we can still understand a surprising amount of detail about their technique. In part, archaeologists approached those questions the same way art students for centuries have tried to learn the techniques of the great masters: namely, by copying their work. Henshilwood and his colleagues marked up numerous pieces of smooth silcrete with ocher crayons and ocher-based paint, trying to replicate the look of the anonymous Stone Age artist’s cross-hatching. The best match came from a soft ocher crayon with a pointed tip about 1.3 to 3.3mm across.
On close inspection, the lines have a sort of patchy appearance, which comes from loose ochre powder falling into the low points and eventually washing or wearing away, while ochre stuck better to the higher, smoother bits of the rock; think about how a modern crayon leaves a patchy, uneven line if it’s drawing on a rough surface. Paint, on the other hand, left a much smoother line that didn’t match the ancient drawing.