Part of the task force for the second revision cycle of the Art and Rare Materials (ARM) BIBFRAME ontology extension, the Manuscripts Subteam has been working to define the role of unique items, such as manuscripts, within the conceptual framework BIBFRAME is built from. Describing manuscripts poses challenges as it requires sets of definitions that can be adapted to objects that, by definition, do not always fit in standardized categories. These unique works and the relationships they may have to other works must be described in such a way that their metadata remains unique but also serves discovery to other resources. Our goal is to extend the ontology to create a system that is flexible enough to be collapsed in on itself when the boundaries between work-instance-item are less distinct but also supports these distinctions where valuable. This presentation will explore the meaning and ontological implications of "uniqueness," the overlapping definitions of manuscripts, and how some of the distinctive characteristics of manuscripts can be expressed within the BIBFRAME ontology.
