The Organization of Chipped-Stone Economies at Piedras Negras ...

times. Complete examples of this form are relatively rare at the site, but fragments are
easily identifiable because of their thickness.
The medium celtiform biface, thick type resembles the large type manufactured
along a smaller trajectory. They are often difficult to differentiate from resharpened, large
celts. This biface often features a finer flaking pattern, which suggests that a different
reduction strategy was used for a tool that could be used for finer or more delicate work.
All are manufactured by direct percussion and usually are made from coarse cherts, but
sometimes finer material for a cleaner, more refined, bit. Similar to their greenstone
counterparts, medium celts may have been more useful in the finer working of wood and
stone. Heavy, hammering wear-patterns on the proximal ends of some of these tools
suggest that they could have been used as chisels.
5.4.1.1.3: Large and medium celtiform uniface (see Figure 5.2 #3 and #12). These types
were manufactured by direct percussion, but on only one face of the tool. The dorsal
surface of a nodule reduction flake was the usual locus of reduction. The ventral surface
of the flake-blank was not worked. They are at least 12 cm long for the large type and 8
cm for the medium type. It is wider at the distal end of the tool than the proximal.
Only a few examples of these artifacts were found at Piedras Negras, but some
were made of local materials, suggesting that they were not always imported from
elsewhere. The term uniface is somewhat of a misnomer for two reasons: (1) because all
stone tools have two or more sides; and (2) because there usually is some modification of
the ventral side of the tool (Figure 5.5). I retain the term because it most accurately
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