The millennia-long use history of triangular bifaces

Relatively small, triangular bifaces often considered to be projectile points have a demonstrable use history that includes the Middle Archaic, Late Archaic, Early Woodland, late Middle Woodland, Late Woodland, and Contact periods of regional archaeology. Radiocarbon dates and other data are used to document this extensive history using the Upper Delaware Valley of New Jersey, Pennsylvania, and New York as a case study. Observed trends are evaluated in a broader regional context. The degree to which triangles of different ages can be distinguished from one another is addressed and suggestions for future research are made.