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

5.4.1.2.3: Medium celtiform uniface (see Figure 5.2 #12; see Section 5.4.1.1.3 for
description).
5.4.1.2.4: Medium oval uniface (see Figure 5.2 #13). This type was 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 between 12 cm and 8 cm long, and are slightly wider at the
distal end of the tool than the proximal.
This tool type is rare at Piedras Negras (2 examples) and is unattested at other
sites examined in this study (Figure 5.7). They are made of a medium-grained, cream
colored chert that probably was not locally procured. The flaking pattern is very fine on
the dorsal face, and the ventral flake scar is retained. The flaking pattern and material
type make it impossible to tell whether hard- or soft-hammer percussion was employed.
They could have been used as large cutting or scraping tools (Aoyama personal
communication 2003). Macrovisual use-wear analysis of the Piedras Negras examples is
inconclusive.
5.4.1.2.5: Medium laurel leaf biface, thin (see Figure 5.2 #14). This type was
manufactured with a direct percussion technique. It is between 8 and 12 cm in length, and
is symmetrical with tapered points on either end of the biface. The proximal end, if one
exists, is slightly wider than the distal end, and may feature remnant cortex. The margins
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