The first residue analysis blind tests: results and lessons learnt

Twenty-eight stone flakes were produced, sterilised and then used for a variety of tasks involving the processing of plants and animal products. Precautions were taken to avoid contaminating the residues. One set of used flakes was stored in sealed plastic bags; the other set was buried in compost for a month and then exposed to open-air conditions for three days. The bagged tools were used for a blind test (Test One) to assess the identification skills of the residue analyst who was not provided with any information prior to conducting the analysis. She obtained a high score for recognition of residues and tasks performed. Test Two used the tools that had been buried in compost and here the aim was to study the effects of acidic, organic-rich deposits on plant and animal residues. The Test Two results intimate that animal residues are more sensitive to certain burial and exposed conditions than plant residues, but more closely controlled experiments are needed before definite conclusions can be drawn.