Fig. 2: Stone artefacts recovered from Early Pleistocene deposits at Calio.

a, Artefact 1: a large chert flake discovered partially exposed on the surface in a heavily cemented conglomerate. A black linear mineral stain marks the boundary between the exposed part of the flake and the portion embedded in the sandstone. b, Artefact 2: a medium-sized retouched flake struck from a core made from brecciated chert. The arrows indicate the direction of retouch scars across the dorsal face. c, Artefact 3: a small flake struck from a water-rolled chert cobble. d, Artefact 4: a small flake with moderate taphonomic (that is, non-cultural) flaking to both faces (it is broken diagonally). e, Artefact 5: the proximal end of a large flake broken by weathering. f, Artefact 6: a medium-sized redirecting flake struck onto a relatively flat cortical surface of a water-worn chert cobble. g, Artefact 7: a heavily abraded flake with moderate to heavy taphonomic flaking to both faces. Scale bars, 10 mm.