Stone-boiling maize with limestone: experimental results and implications for nutrition among SE Utah preceramic groups

► Fire-cracked limestone is abundant at sites of maize-dependent but preceramic groups at Cedar Mesa, Utah. ► Experiments show that local limestone calcines at temperatures achievable in open juniper-fueled fires. ► Experimentally stone-boiling maize with limestone increases availability of essential amino acids. ► Limestone frequency declines greatly in later sites having pottery vessels and beans as a supplemental protein.