Determining Fire-Cracked Rock Function Through Use-Alteration and Fracturing Patterns

This chapter reviews the different performance characteristics of rocks employed as various types of heating elements. Raw materials, which exhibit distinct performance characteristics when heated, are also explored, particularly slate, sandstone, basalt, quartz, quartzite, chert, obsidian, and limestone. Because use-alteration analyses of fire-cracked rock (FCR) are scarce, the chapter describes the thermal processes that affect stone and a range of physical signatures that are useful in the identification of patterns related to FCR use alteration, fracturing, morphology, and size grade. FCR are found in great quantities around the world but they still remain an understudied artifact type. To address this, a range of attributes for the identification of universal use-alteration and fracturing patterns on stone is described in this chapter. The study of these patterns allows for the identification of FCR in the archaeological record, as well as the variation of the material within collections and the forces that shaped their formation. A methodology is included as an appendix at the end of this chapter. It comprises of an attribute list for the analysis of FCR that readers may use as a guide to modify as needed according to their own study.