This paper investigates the effects of heavy shell deposits on the condition of low-fired ceramics using the Late Archaic fiber-tempered assemblage from St. Catherines Island, Georgia. Through combined non-destructive analytical techniques, including variable pressure scanning electron microscopy (VPSEM) and portable X-ray florescence spectroscopy (pXRF), the structural, chemical, and physical deterioration is examined. This study seeks to determine the efficacy and limitations of non-destructive analysis in the investigation of deterioration processes. Limited destructive analysis using thin-section petrography is employed to complement the non-destructive testing. The condition of ceramics recovered from dense shell deposits is compared with those from shell-free areas of the site. The paper discusses the effect that the burial environment has on changes in preservation, as well as the consequences that these changes have on the excavation, storage, and analysis of these materials.