Rare Rocks

Items in the DAP nonflaked lithic tool assemblage and miscellaneous material files that represent “unusual materials of geologic origin” have been collected within a single rare rocks dataset (Keane and Clay 1987:507). More specifically, the dataset contains both naturally occurring and culturally modified items comprised of geological resources that are found in the Dolores Valley, or have been transported over long distances (Keane and Clay 1987). Items fashioned from rare material types are particularly suited for supporting research where prehistoric resource use and exchange networks were concerned and may also have implications for examining the ritual and ideological activities of the Dolores Anasazi (Keane and Clay 1987). It is assumed that DAP conventions for measuring length, width, and thickness in millimeters, and weight in grams were repeated here, but Wilshusen et al. (1999:101) have cautioned that there is limited documentation of how measurements and classifications were actually made. The rare rocks dataset combines similar classes of artifacts that do not neatly fit into other datasets and should be viewed as a catalog of distinctive mineral items; most of their utility will be found in identifying patterns of rare mineral distribution among sites, or finding items that may be difficult to detect in other datasets (Keane and Clay 1987). The material type for each entry is contained within the ID field; items are coded for one of 49 recognized types ranging from minerals to shell and organic matter. Color, streak, and hardness were documented using their respective values from the Munsell color chart and Mohs scale. The special specimen type and number values typically indicate whether items were recovered while processing bulk soil samples, during survey as isolated finds; however, none of these values are applicable to items in the rarerox database. The newid value extends the range of possible material types represented by items in this dataset.

Variables in the rare rocks dataset have been described by Wilshusen et al. (1999); see especially the section "Ornaments, Rare Rocks, and Miscellaneous" by Judy Newland. In most cases, her descriptions are suitable for use as metadata and have been repeated almost verbatim here. See also Chapter 21, "Geological sources of unusual minerals and rocks of the Dolores Project area," by Stephen P. Keane and Vicki L. Clay, in Supporting Studies, Settlement and Environment.