During the spring, 1985, the U.S. Bureau of Land Management (BLM) and the New Mexico Bureau of Mines and Mineral Resources (NMBMMR) entered a cooperative agreement to prepare a preliminary mineral-resource inventory and assessment of northwestern New Mexico, including Valencia, Cibola, McKinley, San Juan, and western Rio Arriba Counties. This is the third of. six reports describing the geology and mineral-resource potential of northern New Mexico. The first report describes the methodology and classification of mineral-resource potential used in this report and includes a summary of the mineral-resource potential of Cibola County. These reports are based upon time consuming analyses of all available data, published and unpublished, by a group of geologists and technical support staff. Without this team effort this project would be impossible. In addition to the coauthors of the final report, many other people at the NMBMMR and BLM provided assistance, especially in reviewing the rough drafts. This report is organized into a text, appendices, and supporting figures, maps (scale 1:100,000), and tables. Known mineral occurrences, mines, and deposits, including material pits, are briefly described in Appendix 1 and plotted on 1:100,000 scale maps. Mineral-resource potential of various commodities is discussed in the text and also shown on 1:100,000 scale maps.