A small stemmed projectile point from western Massachusetts possibly dating to the Late Woodland Phase (1100–300Â years ago) but of unknown age (but in any case less than about 18,000Â years old), was fabricated from a locally available crystal of orthoclase feldspar derived from granite or granodiorite. Fabrication of the point demonstrates a fairly sophisticated appreciation of the sculpting potential inherent in a potassium feldspar megacryst. Use of intact single crystals found in the environment by organisms has a long history on earth, dating back at least to the Cambrian Explosion. Between Phase I of crystal utilization (Proterozoic-Early Cambrian) and Phase II of crystal utilization (Homo sapiens crystal usage) is what is called here the Crystal Gap, a long stretch of geological time during which there is no evidence for use of discreet types of crystals by animals that have intentionally selected minerals of particular compositions from their environment.
CITATION STYLE
McMenamin, M. A. S. (2018). Feldspar point. In Springer Geology (pp. 261–270). Springer. https://doi.org/10.1007/978-3-319-74256-4_12
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