Grid and inventorying

The reference grid needs a word of explanation. In front of Cueva Negra (itself 12x12 m across) a terrace runs NE from a cliff-like extension of the west wall (Figure 3). To include the terrace, the reference grid's columns of 3x3 m squares are given capital letters from west to east (i.e. from right to left) and its rows are numbered from the back of the cave outwards on to the terrace (Figure 3b). Each 3x3 m square is subdivided into nine 1x1 m squares identified by small letters (Figure 3b), so every metre square is uniquely and unmistakably identifiable (e.g. C3e, A4a, D4c, etc.).

The stratigraphical units are both numbered from above down, and their excavated spits are defined by small letters (suppressed in Figure 4 where vertical subdivision is limited to upper and lower halves of unit 2). Unit and spit are bracketed together for inventorying finds - thus (2h), (3f), (4b), etc., and each metre square and spit have two inventories that are unique to them, one for each mineral piece found ("M"), the other for each bone or tooth found ("H" = "hueso" = bone) e.g. C3e(2h)H0047, A4a(3f)M0018, D4c(4b)M002, etc.. Hominid remains alone are also individually numbered: CN-1, CN-2, CN-3, etc.. Rapid data-base manipulation of lithic or faunal finds is achievable, both by 3x3 m square and unit, and also by 1x1 m square and spit. By contrast, at Sima de las Palomas, the disparity of locations and raw materials knapped, and the small proportion from stratigraphically sealed situations, favoured an inventory giving such aspects pride of place.