The U.S. Bureau of Mines studied the 3,500-acre Winegar Hole Study Area, Idaho, a legislatively proposed (101st U.S. Congress) addition to the Winegar Hole Wilderness, WY; it adjoins the western boundary of the wilderness at the Idaho-Wyoming border, about 15 miles east of Ashton, Idaho. The study was part of an Idaho Land Assessment Program to provide minerals information for land-use decisions and ensure domestic mineral supplies. The study area is an east-west elongated, wooded plateau south of Falls River. Although the area is covered with surficial glacial deposits, it is probably underlain by volcanic flows; light-colored and Mafic flow rock were noted in sparse outcrops. No mines, prospects, mineralized areas, or mineral resources were found in the study area during a literature and field search. The only nearby prospects include geothermal and rock aggregate (volcanic cinder) sites and several placer claims. Although the winegar hole study area lies within a region of potential geothermal resources, no evidence of geothermal acitvity was observed. Rock in the area does not split into flat slabs that could be useful as dimension stone, and would require crushing to be used as aggregate. Alluvium (placer) samples contain less than $0.01 per cubic yard gold (at a $350 per oz price); alluvial deposits are too small to contain gold resources.