Published online by Cambridge University Press: 20 January 2017
Radiocarbon determinations on marine shell have previously been used to provide evidence assigning a fourth to sixth millennium B.C. age to ceramic objects excavated at the Irvine site, an early Archaic period shell midden located in coastal southern California. Objections have been raised concerning the reliability of the stratigraphic association of ceramics and the radiocarbon-dated marine shell materials. An examination of the thermoluminescence responses of two ceramic samples resulted in minimum TL ages of ca. 1500 B.C. Evidence for a presumably indigenous California ceramic tradition may also be present at two additional sites. This suggests that the arrival of ceramic forms into southern and central California by way of the southern Great Basin and Colorado River may be seen as a separate, comparatively recent [ca. A.D. 1000] phenomenon.