Amorphous silica, soil solutions, and archaeological flint gloss

natural chemical processes in soils produce glossy conditions on artifacts of flint and chert that mimic, modify, or destroy ancient use-wear traces, thus making affected artifacts difficult or unacceptable for microwear stud ies. These glosses include general gloss patina or soil sheen, and intensel y brilliant specular spots. The information presented suggests that this en igmatic 'bright spot' phenomenon is the result of deposition and solidifica tion of silica gel precipitated from soil colloids in the artifact's in sit u environment and should not be confused with ancient use-wear evidence.