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.