Red ochre is a dye made from the mineral hematite (Fe₂O₃). It's use by ancient humans is generally assumed to be ritual, though modern humans use it as a medicine, a food preservative, an insect repellent and in tanning leather, and its use as an adhesive in ancient sights has been documented; any of these uses would represent reasonably sophisticated behavior. Early modern humans in East and Southern Africa are known to have been using Red Ochre from about 160 000 years ago onwards, and Neanderthals from about 60 000 to 40 000 years ago - around the time they would have been encountering modern humans, which makes it possible that they could have learned the behavior from our ancestors. There have been a few prior claims for more ancient use of Red Ochre in Europe, but all of these have been disputed either in the age of the site or identification of the dye.
The 7 February 2012 edition of the Proceedings of the National Academy of Sciences contains a paper by a team of scientists lead by Wil Roebroeks of the Faculty of Archaeology at Leiden University, describing the discovery of Red Ochre at the Maastricht-Belvédère Loess and Gravel Pit palaeoarchaeological site in the Netherlands.
Samples of Red Ochre from the Maastricht-Belvédère site. From Roebroeks et al. (2012).
The Maastricht-Belvédère site has been studied since the 1980s and is extremely well understood, a variety of dating methods have bee used at the site, including bio-stratigraphy based on small mammals and molluscs (small animals often have high species turnovers, making it possible to date sites by the presence of animals), and chemical dating techniques, all of these suggest the site is at least 200 000 years old, and probably over 250 000 years old.
The site is located in a river valley near the modern city of Maastricht. It appears to have been a significant site for the production of flint tools; items thought to have come from the area have been found as far away as the Rhine Valley. Hematite is not local to the area, and would have to have been brought in from tens of kilometers away. This combined with the known export of flints from the site suggests that a reasonable sophisticated system of economic exchange may have been operating at the time when the site was in use.
Map of the location and surrounding area. Site is at Maastricht. Brown areas indicate sources of hematite. Darker green areas are more than 500 m above sea level. Flint artifacts from the site have been found along the arrow. From Roebroeks et al. (2012).
The red ochre appears to have been made into a thick solution or paste by grinding hematite and mixing it with water, it was found at a number of locations on the dig site, where it appeared to have been spilled of dropped in distinct splodges. This is unlikely to have been a natural deposition process; occasional floods in a river valley would give very thin but widely spread layers of the mineral. This suggests that the ochre was definitely introduced to the site as a result of hominid activity, probably from some distance away (although a closer source no longer available cannot be ruled out).
