Ancient cultures have used ochre, a naturally occurring clay mineral, in a variety of ways. It was used decoratively, to adorn the body or as a base pigment for many famous Paleolithic cave paintings. It was also used more pragmatically, as a sort of sunscreen, a way to disinfect wounds, and an ingredient in glue. Ochre was even used ritualistically, as a part of burial ceremonies.

We know this because ochre appears fairly often in the archaeological record, for several reasons. Firstly, homo sapiens have long been fascinated by color. “Almost as soon as [modern] humans start to emerge,” some 200,000 to 300,000 years ago in Africa, says Needham, “you start to see evidence of their manipulation of color.” Sites like Pinnacle Point in South Africa, for example, reveal humans using crayon-like objects as early as 160,000 years ago.

Secondly, ochre is a very stable substance. “If you made pigments from plants, like berries, it would be much more short lived,” he notes. “Of the whole sea of [substances] you might use to produce color, ochre is one material that preserves particularly well.”