Grey zones of production. Discussing the technology of tools on chert quarry (Lojanik, west-central Serbia)

Flaked stone artefacts found at mines and quarries are usually classified as non-diagnostic pieces. The Lojanik opal and silicified wood mine in West-Central Serbia is a good example of how through technological analysis, initial parts of the reduction process could be determined. This problem should be approached very cautiously since the mine has been exploited over a wide time range, from the Palaeolithic, through the Neolithic to the Copper Age. In this study, we will present the particular clusters of artefacts. These groups are formed based on the spatial distribution from the extraction zones, followed by massive deposits of raw materials, to the workshop areas for cores, tools or just for processing one type of opal. Our attention is focused on the prevailing category of fragmented raw materials in the initial phase of knapping, preforms, debris, broken pieces of anthropogenic origin and an immense number of artefacts-ecofacts. The last category is significant because sometimes it is very difficult to distinguish human action from post-depositional processes created by opening and abandonment of mining work. It happens that this non-diagnostic group of debitage is sometimes the only indication for the recognition of archaeological ore zones.