- Covada Mining District (Enterprise Mining District)
| Derkey, Robert E., Joseph, Nancy L., Lasmanis, Raymond (1990, November) Metal Mines of Washington - Preliminary Report. Open File Report 90-18. Washington Division of Geology and Earth Resources Cannon, Bart (1975) Minerals of Washington. Cordilleran, Mercer Island, WA. Valentine, Grant M., Huntting, Marshall T. (1960) Part II - Metallic Minerals, in Inventory of Washington Minerals. Vol II. Bulletin 37, Washington Geological Survey. |