Fig 1.
Location of Marathousa 1 and the localities where radiolarite for the experiment was collected in the Megalopolis basin (Peloponnese, Greece).
The grey-shaded area marks the extent of the mines where lignite is being explored for commercial purposes. The elevation data are derived from the Shuttle Radar Topography Mission (SRTM) 1 Arc-Second Global DEM. Geographical features are based on OpenStreetMap (OSM) data using the OSM plugin in QGIS 3.34.10 [22]. The administrative boundary for the inset map of Greece is from the Natural Earth dataset (https://www.naturalearthdata.com/). The stratigraphic column is adapted from [23].
Fig 2.
Attributes considered for technological analyses.
Table 1.
Attribute Definitions and Scoring Criteria for Flake Analysis.
Fig 3.
These pictures depict examples of the tasks by the authors. The first row represents the three percussion techniques utilised: freehand, bipolar-on-anvil (sensu [48]), and bipolar anvil-assisted. The second row shows a sample of the pebbles collected in the Megalopolis basin, the hammerstones and the anvil utilised for bipolar techniques.
Fig 4.
Boxplot showing the differences in length (mm), when comparing artefacts made on radiolarite to those made on other raw materials.
Fig 5.
Scatter plot comparing the median values of exterior platform angle (EPA) and platform width (based on data published in [76]; see link to open access data below).
Bigger flakes in the plot indicate greater platform depth and broader external angle. From this perspective, Marathousa 1 shows very small flake dimensions compared to other Middle Pleistocene sites, while its median platform depth mostly overlaps with Late Pleistocene sites [76] (data available at https://zenodo.org/record/1408081#.W6iyn84zaHs).
Fig 6.
a) Flake with platform preparation and traces of proximal trimming, possibly detached to assess the flaking surface after a step fracture visible on the negative of a previous unidirectional removal. b) Target flake or edge modification flake with proximal preparation, unidirectional pattern and natural notch on the distal due to an impurity. c) Chip from retouch. d) Flake with platform preparation and central convexity produced through a centripetal pattern. e) Flake with sub-central ridge and double platform due to the presence of cleavage planes. f) Chip from retouch. g) Target or retouch flake with platform preparation. 8) Production or confection flake with orthogonal negative on the dorsal surface.
Fig 7.
Flakes in other raw materials.
a) Mudstone flake. b) Limestone point from centripetal reduction. c) Limestone elongated pointed flake with unidirectional pattern and use-wear traces. d) Limestone robust flake. e-f) Flint flakes obtained from bipolar percussion.
Fig 8.
Naturally backed knives and core edge elements (1-6).
Fig 9.
a) Convergent denticulate on flake. b) Median flake fragment retouched in convergent tool with resharpening traces. The arrow indicates the axis of percussion. c) Retouched tool on a cortical piece, with a natural back opposite a notched edge. d) Scraper on a semicortical pebble fragment. Flake and chip negatives exhibit patterns consistent with those in the assemblage. e) Carinated scraper on a subangular pebble fragment. The negatives of flakes and chips produced during retouching exhibit patterns consistent with those observed in the assemblage. f) Retouched tool with a rectilinear edge opposite a backed edge. g) Retouched pointed tool. h-i) Denticulate on flake. j) Notch on cortical bipolar flake. k) Heavily reduced denticulate on a cortical pebble fragment.
Fig 10.
Expedient tools on debris and natural blanks.
a) Backed knife on radiolarite tabular piece. b) Notch on limestone blank. c) Pointed tool obtained through two alternate removals on tabular mudstone blank. d) Notch on chunk with convergent shape. e) Chunk with serrated retouch (and possibly use-wear) on two larger alternate removals which form a spine. The removals occur on two opposite surfaces (from the cleavage plane and the side of the piece).
Table 2.
Comparison of archaeological flakes and chips (≥10 mm) attributed to bipolar-on-anvil and freehand techniques.
Fig 11.
The pieces generally originate from pebble fragments during the initial stages of reduction, except for d, which possibly represents a cortical exhausted bipolar core oriented vertically.
Fig 12.
Examples of radiolarite cores.
a) Unidirectional sub-pyramidal exhausted freehand core. b) Exhausted multidirectional core. The core exhibits bipolar reduction traces with chips removals in its final phase. c) Core fragment with unipolar removals of flakes produced through freehand technique. It is attributed to the same original reduction sequence as three refitted flakes (Fig 15: 2), although these flakes do not directly refit with the core itself. d) Exhausted bipolar core with multiple crushing traces. The core exhibits irregular removal of chips, possibly as a means of shaping an active edge for use as a tool. e) Exhausted core with multiple flaking surfaces, possibly resulting from freehand reduction. Removals along one side of the core can be related to shaping a functional edge, suggesting a transition from a core to a potential tool. f) Pointed tool on an exhausted multidirectional core with flake and chip removals. The scars are consistent with other chips and flakes found in the assemblage (e.g., Fig 6d). f) Core with a converging morphology at opposite ends, likely resulting from bipolar reduction, with possible subsequent reshaping as a tool. h) Exhausted core with a multidirectional flaking pattern and evidence of bipolar reduction. The pointed morphology results from two opposing flake removals, while a larger flake detachment on the opposite surface has thinned the tip area, possibly enhancing its functionality.
Fig 13.
PCA based on linear metric data.
The eigenvalues and loadings are listed in Table 3.
Fig 14.
CATPCA based on qualitative flake attributes.
The eigenvalues and loadings are listed in Table 4.
Table 3.
Statistics of the PCA presented in this study. The factor loadings are represented by length (L), width (W), thickness (T), platform depth (PD), platform width (PW).
Table 4.
Statistics of the CATPCA presented in this study. The factor loadings are represented by the bulb of percussion (BP), flake termination (FT), sharp edges (SE), central crest/ridge (CC), platform preparation/trimming (PP), and ripples (R).
Fig 15.
Marathousa 1, refits and conjoins.
a) Refit of an elongated flake with a flat ventral surface and exhausted core, both associable with bipolar reduction. b) Refit of three unidirectional small flakes, obtained through freehand percussion, likely belonging to the core fragment of the same RMU. c) Refit of a pointed flake with an orthogonal small flake removal. The latter functions as a confection flake, intentionally detached to create a notch on the main piece. d) Refits of an orthogonal chip (with conjoin) and a flake, possibly detached for thinning or convexity management.