Technical microwear and residues in identifying bipolar knapping on an anvil: experimental data

The functional study of the stone tool artefacts from the Middle Pleistocene site of Isernia la Pineta (Molise, central Italy) revealed microtraces that display certain features that did not fit in with what we know as use-wear traces. The suspicion that these microtraces may be technical traces derived from bipolar flaking, which is prevalent at this site, led us to initiate an experimental programme to check our hypothesis. The experiments conducted allowed us to identify residues associated with bipolar flaking on an anvil and to characterise the microscopic traces derived from this production technique. Our results proved very useful in identifying the artefacts produced by bipolar flaking, as well as in determining the basic lithological features of the anvil. Moreover, these experiments allowed us to assess the possible interferences that these kinds of technical traces can cause when performing the functional analyses of lithic assemblages produced by the bipolar technique.

Research highlights
► We present the results of an experimental programme on bipolar knapping on an anvil.
► First we study the mechanics of bipolar flaking and the variants of the technique.
► We describe under SEM the resulting technical deposits of residues and microtraces.
► These traces can easily mimic usewear traces and, so, interfere functional studies.