Temper mixture models and assessing ceramic complexity in the emerging Tarascan state

This study presents compositional data from ceramics drawn from surface survey and controlled excavations from three prehispanic sites within the relatively small Lake Pátzcuaro Basin, representing a ceramic sequence stretching nearly 1500 years, from the Preclassic to Late Postclassic Tarascan state (ca. 50 B.C.–1525 A.D.). Using neutron activation analysis, we identify compositional groups and model the importance of volcanic materials as temper in the construction of prehispanic ceramics by matching mathematical simulations of clay–ash mixes to the compositional groups. Rather than discreet clay resources and spatially circumscribed production, we argue for a broadly dispersed and highly varied organization of pre-Tarascan and Tarascan state ceramic production in which the potters' distribution and use of specific volcanic ashy additives, not clays, structured the organization of production.