“…Competitive interlocking market systems tend to feature many markets and goods that flow freely through them. The northern lowlands in the Postclassic period is generally thought to exemplify this type of system (Freidel and Sabloff 1984;Freidel 2012, 2013;Sabloff and Rathje 1975) and Braswell has suggested that the Terminal Classic period, where obsidian from the same broad variety of sources was available at both Uxmal and Chichén Itzá, also pertains to this category. This kind of source analysis does not work well for the northern lowlands in the Early Classic period since the El Chayal source dominates obsidian at all sites.…”