Preliminary map showing limonitic areas in the Silver City 1 degree by 2 degrees Quadrangle, Arizona and New Mexico

This map is a part of a folio of maps of the Silver City 1^o x 2^o quadrangle, Arizona and New Mexico, prepared under the Conterminous United States Mineral Assessment Program. As a part of this study Landstat images were used to map the anomalous areas of limonitic materials as a guide to hydrothermal alteration which, in turn, acts as a guide to mineralized systems. The term limonite, defined by Blanchard (1968) as a general term for undifferentiated ferric oxide percipitates, is here modified to include any mineral with the typical spectral reflectance properties of the ferric oxide minerals such as hematite and goethite, as defined by Hunt (1980). The nap shows anomalous areas of limonitic miaterials that might be associated with mineralization.