Epifluorescence Microscopy of Experimentally Heated Animal Bones: Applications to Archaeological Micromorphology

Summary

This is an abstract from the "Charred Organic Matter in the Archaeological Sedimentary Record" session, at the 84th annual meeting of the Society for American Archaeology.

Burned bones are an important constituent of the archaeological sedimentary record. Their presence is usually indicative of human activity and may provide information about past human behavior.

In micromorphological thin sections, charred bone fragments may appear as opaque and amorphous, and extremely difficult to distinguish from other organics related to fire activities.

As bones emit a green fluorescence upon irradiation with UV-blue light, epifluorescence microscopy can provide a solution to this problem. To our knowledge, no rigorous studies have ever been performed on fluorescence properties of heat-altered bones in thin sections.

We have experimentally heated animal bones in a muffle furnace under oxidizing conditions at different temperatures between 100 and 700 ºC; and subsequently prepared sets of polished samples. We investigated their fluorescence properties with a customized epifluorescence microscope: by attaching a spectrometer to one of the oculars, we could record emission spectra for specific regions in the microscope's field of view, hence objectively describing color.

Our preliminary results show that at each temperature, bone is characterized by a unique emission spectrum, indicative of the heat-induced chemical and structural changes within the bone. Understanding these changes may allow us to interpret archaeological bones in thin sections in new ways.

This Resource is Part of the Following Collections

• Charred Organic Matter in the Archaeological Sedimentary Record   •
• Society for American Archaeology 84th Annual Meeting, Albuquerque, NM (2019)

Keywords

Record Identifiers

Abstract Id(s): 25481