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

of these materials are nodular flints, marked as such by decortication flakes and finished
tools with remnant chalky cortexes 10 . The material also has a fine, waxy gloss. If these
materials are local, the source has not yet been identified. The existence of fine nodule
decortication flakes suggests that nodules may have been traded intra- and inter-
regionally, and not just finished flakes or bifaces. The fine, imported microcrystalline-
quartzes resemble those from other areas of the western Maya Lowlands. Opaque, dark
brown flints are very similar to those found along the Pasión River, such as
microcrystalline-quartz eccentrics from Altar de Sacrificios. Some bifacial points made
of fine grey cherts (Figure 4.2) are similar to those made at Cancuen (Kovacevich 2003).
It is possible that sites with ready access to fine microcrystalline quartzes, such as
Cancuen and Altar de Sacrificios, produced fine bifaces for exchange beyond their own
polities. Similar exchange systems have been described for the fine honey-brown cherts
of the chert-bearing zone of northern Belize. The main products produced for trade in that
area, however, were celtiform axes, eccentrics and macroblades. None of these artifact
types, nor any Colhá-type materials, have been found at Piedras Negras.
Some extremely coarse-grained materials and nonlocal cherts also are common at
Piedras Negras and may represent one or more unidentified tool-stone sources of regional
importance. A medium-grained cream-to-tan chert is particularly common, and tools
made of this material, and other imported coarse-grained microcrystalline quartzes,
represent over half of the entire sample. It is clear that some of the imported materials
arrived as nodules because of the frequency of decortication flakes and early biface-
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