Investigating freshwater mussel (Unionidae) shell diagenesis at an archaeological site on the Tombigbee River, Mississippi, southeastern U.S.A

Abstract Multiple microscopy methods, including thin sections, SEM, confocal, and cathodoluminescence, were used to examine two strata of freshwater mussel shell at the Vaughn Mound site (22LO538) in Mississippi, southeastern USA. These two strata are separated significantly in age. Specimens from the older stratum show evidence of physical alteration (pitting, dissolution, etching) that likely explains previously noted chemical differences observed between the two strata. These results emphasize that characterizations of diagenesis should be included in any study involving the chemical sourcing of shell artifacts or shell-tempered ceramics.