Provenance, modification and use of manganese-rich rocks at Le Moustier (Dordogne, France)

Abstract

The use of colouring materials by Neanderthals has attracted a great deal of attention in recent years. Here we present a taphonomic, technological, chemical-mineralogical and functional analysis of fifty-four manganese rich lumps recovered during past and on-going excavations at the lower rockshelter of Le Moustier (Dordogne, France). We compare compositional data for archaeological specimens with the same information for twelve potential geological sources. Morphometric analysis shows that material from Peyrony’s excavations before the First World War provides a highly biased picture of the importance of these materials for Mousterian groups. These early excavations almost exclusively recovered large modified pieces, while Mn-rich lumps from the on-going excavations predominantly consist of small pieces, only half of which bear traces of modification. We estimate that at least 168 pieces were not recovered during early work at the site. Neanderthals developed a dedicated technology for processing Mn-rich fragments, which involved a variety of tools and motions. Processing techniques were adapted to the size and density of the raw material, and evidence exists for the successive or alternating use of different techniques. Morphological, textural and chemical differences between geological and archaeological samples suggest that Neanderthals did not collect Mn-rich lumps at the outcrops we sampled. The association and variability in Mn, Ni, As, Ba content, compared to that observed at the sampled outcrops, suggests that either the Le Moustier lumps come from a unique source with a broad variation in composition, associating Mn, Ni, As, Ba, or that they were collected at different sources, characterized either by Mn-Ni-As or Mn-Ba. In the latter case, changes in raw material composition across the stratigraphy support the idea that Neanderthal populations bearing different stone tool technologies collected Mn fragments from different outcrops. Our results favour a use of these materials for multiple utilitarian and symbolic purposes.

A new experimental methodology for assessing adhesive properties shows that Neandertals used the most suitable material available

“…Neandertals were likely deliberately selecting manganese dioxide at Pech-de-l'Az e I due to its beneficial use in fire starting by reducing the autoignition temperature of wood (Heyes et al, 2016). At Le Moustier, there is evidence Neandertals developed specific technology, adapted to the size and density of the raw material, for processing similar manganese-rich rocks (Pitarch Martí et al, 2019). At Poggetti Vecchi, Italy, boxwood (Buxus sempervirens), the hardest and densest of all European woods, was likely chosen based on its favorable material properties.…”

The earliest unambiguous Neanderthal engravings on cave walls: La Roche-Cotard, Loire Valley, France

“…In contrast to the lower extremities of the engravings, the upper extremities are well defined here, reaching or even exceeding the second film of the wall alteration. (1,2,9,11,12,13,24,42), and, at the bottom, a set of 21 finger traces (from 63 to 83), only slightly accentuated (contours noted in dashes). These ~10 to 13 mm wide lines are often oriented obliquely, either to the right or to the left.…”

“…However, symbolic productions attributed to Neanderthals are few in number; these include, for instance, engravings on bones or pieces of rock [1], variably transformed shells [2,3], and the possible use of feathers and raptor claws [4]. Use of pigments may also fall in this category, although pigments could have a utilitarian function [5][6][7][8][9]. Other activities are represented by examples with no apparent equivalent, such as a complex object made of stone and bone [10,11], or the appropriation of the underground environment represented by architectural construction inside a cave.…”

First identification of an evolving Middle Stone Age ochre culture at Porc-Epic Cave, Ethiopia

“…Others have focused on the techniques used to modify ochre 17 – 21 . Still others have tried to combine these different approaches at multistratified sites in order to obtain an integrated vision of how the use of this material changed over time 22 , 23 . However, very few sites have been studied from this perspective since ochre, until recently, was not always systematically documented, and the number of ochre pieces found at most sites is inadequate to establish with certainty whether observed evolutionary trends are real or correspond to random changes in insufficiently documented behavioural variability.…”