The East Yuba and West Yuba Roadless Areas, which are located in the northern Sierra Nevada, California, have been evaluated on the basis of geologic, geochemical, and geophysical investigations and an investigation of mines, prospects, and mineralized area. Both areas have demonstrated resources of gold and locally associated silver, in lode and placer deposits in areas of substantiated gold and silver resource potential. Large areas having a probable gold placer resource potntial exist where Tertiary gravel deposits lie beneath Tertiary volcanic rocks in the roadless areas. There are active lode and placer gold mines in the roadless areas. Two areas of substantiated resource potential for small deposits of iron occur in the East Yuba Roadless Area. Each roadless area has an elongate area of probable resource potential for small deposits of chromite. There is little promise for the occurrence of energy resources in the roadless areas.