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

obsidian. Generally speaking, large tools were reduced using direct percussion, and
pressure flaking was used or small tools. Medium tools could be formed through a
combination of both of these reduction techniques, including indirect percussion. Indirect
percussion, however, was a much less common technology, and was often reserved for
microcrystalline quartz and obsidian eccentrics (Titmus and Woods 2003.
I use the more general term of bifacial reduction instead of bifacial thinning,
because, for many bifaces, thinness was not a desired quality. For thick celts and laurel
leafs, for example, a biface-thinning flake would reduce the strength, stability, and
longevity of the use-life of a tool.
Finally, I also describe tool types that are not found at Piedras Negras. My goal is
to provide basic type descriptions for the entire Maya Lowlands that may more easily
enable cross-site comparison. I wish to show which tool morphologies were not selected
by the Maya of Piedras Negras in the hope that future studies may reveal why this may be
the case.
5.4.1.1: Large-sized artifacts (12 cm and longer in length).
5.4.1.1.1: Large celtiform biface, thin (see Figure 5.2 #1). Artifacts of this type were
manufactured by direct percussion. They are at least 12 cm long, and are wider at the
distal end than the proximal. Some of the edges may be finished with pressure flaking. A
thick, diamond-shaped cross section was not a desired result of the reduction process.
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