Lithic Raw Materials in the Lower Rio Grande Valley, South Texas and Northeast Mexico
Analysis of 976 lithic artifacts from twelve museum and private collections in the Lower Rio Grande Valley revealed a preference for seven rock types. Sixty nine percent of all tools were made from gravel chert, which is locally the most abundant rock type on the Frio and Goliad Formations, as well as on the gravels of the Rio Grande. Representing less than 10% each were, the local El Sauz Chert, a black banded metamorphic rock, volcanic rocks, agates, silicified wood, limestone and black chert. Variations in the relative proportion of each rock type are observed by location, suggesting a tendency to use other suitable rocks that were locally available. Contrary to what has been suggested an abundance of lithic resources were available to stone tool makers in the Lower Rio Grande Valley. This study underscores the value of working with collectors in regions where little archaeological research has been conducted.
Brandi Reger, Juan L. González & Russell K. Skowronek (2020): Lithic Raw Materials in the Lower Rio Grande Valley, South Texas and Northeast Mexico, Lithic Technology, DOI: 10.1080/01977261.2020.1765109