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

probably was on a smaller scale than other production locales in Piedras Negras at that
time. These residential groups do not appear to be involved in obsidian blade production
at any other time.
In a similar way, PN24 and PN25 do not provide strong evidence of obsidian-
blade production at any time. PN25, which is located on the east side of the acropolis,
may have been involved in blade production during the Chacalhaaz phase, but only
further excavation in this group can determine whether the initial production pattern
holds. For this study, however, PN25 is marked as a blade producer during Chacalhaaz
times. PN24 is problematic in the sense that there is such a low proportion of production
debitage in the lithic samples. It is possible that the residential group of PN24 was
involved in blade production during the Yaxche phase, but it has a low production value
score, and a low proportion of blade-production debitage to other obsidian artifacts. One
possible explanation for the existence of scant production debitage in the PN24
excavations is that it was closely connected to the acropolis during Yaxche times (see
Fitzsimmons and Muñoz 2001; Golden and Muñoz 2005). Royal garbage was deposited
around this household group, and the production debitage may have originated from
acropolis. PN24 remains problematic as a producer for the Yaxche phase, but is an
excellent example of a blade consumer during Chacalhaaz times.
In contrast to the PN24 excavations, the residential groups of PN23 and PN33
appear to have been involved in obsidian-blade production over a long period of time,
and perhaps with a greater intensity than other areas of the site, especially the U Group
(Operation PN33). The U Group yielded almost three times more obsidian artifacts than
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