The Rock Wren Locality
A well-formed chalcedony biface was recovered 50 cm below the surface in the side of a drainage channel incised into a late Pleistocene nested unit of alluvium at a location approximately 100 m ENE of Master Pit I at the Calico Site. The specimen’s face and edge modifications reflect a technique of controlled knapping not evident on either the surface artifacts of the Lake Manix Lithic Industry or the late-middle-Pleistocene-age Calico specimens.
Because the specimen was discovered during a hike on which a rock wren nest was found, it has come to be euphemistically called the Rock Wren biface; the adjacent 3-m x 3-m test excavation is called the Rock Wren Test Pit.
Thermoluminescence analysis of sediments stratigraphically equivalent to the base of the biface indicated deposition occurred 14,400 (Â±2,200 years) b.p. (Debenham 1998). This date and its error factor suggest that the Rock Wren Biface is of an age equivalent to Clovis or slightly earlier.