Dacite is a very fine-grained raw stone material created by volcanic action, and used by flint-knappers in the northern Rio Grande valley of New Mexico and southern Colorado. Initially identified by archaeologists as 'basalt', this volcanic stone is more fine-grained than basalt, and knaps easily.
Dacite found in prehistoric contexts in the Rio Grande such as Pot Creek Pueblo have been identified by chemical analysis and identification of trace elements as having come from several locations in the Taos Plateau Volcanic field, including Newman Dome and the San Antonio Mountain; and the Cerros del Rio chill zone, both areas in northern New Mexico.
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