Figure 4

Use-wear and residue analyses of sample 3 found in Layer 6B at Saradj-Chuko grotto. (A) Photo of sample 3, scale bar = 1 cm. The arrows indicate position of close-ups of residues and use-wear traces shown on microscopic photos 1–3, scale bar = 1000 μm: (1) residues of black substance (bitumen) on the tool base, (2, 3) polishing and spin-off fractures on the tip. (B) SEM close-up on a sample of the black substance (bitumen residue) analyzed by FTIR and Raman spectroscopy, and Raman spectra of three residue samples. (C) FTIR spectrum of the same residue.