Identical rock types with different chemistry: Sourcing phyllite-tempered Hohokam pottery from the Phoenix basin, Arizona

The organization of ceramic production and distribution among the ancient Hohokam of the Phoenix basin, Arizona, has been documented in recent years with much detail. Based on diverse temper and clay compositions, the provenance of individual ceramics is routinely determined with considerable precision. One exception is phyllite-tempered pottery, which was made in one corner of the basin but also across a broad upland zone adjacent to the north. The phyllite-tempered pottery from different production sources cannot be distinguished on the basis of their temper type. As shown with assays with an electron microprobe, however, both the temper and clay fractions are chemically diverse and geographically distinct, allowing many of the phyllite-tempered wares to be sourced. Among the phyllite-tempered ceramics consumed in the Phoenix basin, some are shown to have been made locally, but, surprisingly, large numbers were imported from the northern uplands. Their numbers support the idea that the connection between the Phoenix basin and the northern uplands was a prominent component of the Hohokam regional economy despite the great difference between them in settlement size and density.