International Protocol for the Study of Amorphous Charred Objects in Archaeology (IPSACO 1.0)

Abstract Archaeobotanists around the world increasingly recognise that, alongside commonly studied materials such as seeds, fruits, wood charcoal, and chaff, archaeobotanical samples also contain fragments of carbonised organic (and sometimes inorganic) matter that vary in shape and often display an amorphous structure. These amorphous charred objects (ACO) are emerging as a novel proxy within the broader field of plant macroremain studies in Archaeology. Recent research has demonstrated that ACOs can yield invaluable information on key aspects of past human life, including diet and cooking practices, the exploitation of “missing” food resources, such as roots and tubers, and the origins of widely consumed foods like bread and beer. However, as a relatively new field of research, the study of ACOs still faces significant methodological challenges, foremost among them the absence of universally accepted analytical procedures, shared terminology, and classification systems. In this paper, we have brought together a group of international experts to address these limitations by creating the first “International Protocol for the Study of Amorphous Charred Objects” in Archaeology (IPSACO 1.0). This protocol is designed to provide both specialists and researchers seeking to become familiar with the study of ACOs with the necessary tools to ensure standardised analysis, description, and interpretation of these materials, regardless of their category, chronology, or geographical context. We regard IPSACO 1.0 as a key step towards establishing a robust methodological framework for the analysis of ACOs in archaeological research. This first version of the protocol is intended as a living document: it will be revised, expanded, and refined over time to incorporate new analytical procedures and tools, and to ensure that data generated in ACO studies is standardised, transparent, and reusable within the archaeobotanical community and beyond.