HOW MANY SHAFTS WERE DUG AT ONCE?

Many quartzite blocks and boulders were brought to Casa Montero from the nearby banks of the Rivers Jarama and Henares for use as hammerstones. These became fractured with use in the different processes of flint extraction and working, and were dumped into open spent shafts along with mining waste. They are much fewer in number than the flint wastes, however, and can therefore be reconstructed. Investigation has shown that many of the shafts within a 10 x 10 m sampling unit (21 shafts in one of these units) were filled during a single period of mining activity. Two fragments of pottery that fitted together, but which came from shafts 60 m apart, suggest some of these activity periods were rather intense