by W.F. Giannini and P.C. Sweet., 8.5 x 11-inch soft-cover book, 28 pages, 14 figures, 2 tables, 1 appendix, 1991. Tantalum- and niobium (columbium)-bearing mineral series which contain the major sources of tantalian and niobian metals in Virginia are tantalite or columbite, wodginite, and pyrochlore or microlite. Minerals that contain minor amounts of tantalum or niobium include euxenite or aeschynite, samarskite, fergusonite, cassiterite, and wolframite. Seventeen samples from eleven sites in eight counties (Amelia, Bedford, Charlotte, Goochland, Pittsylvania, Powhatan, Prince Edward, and Rockbridge) in Virginia were examined to identify the tantalian and niobian minerals; a maximum of 46.8 percent tantalum (Ta2O5) and 76.9 percent niobium (Nb2O5) was found in the samples. Brief descriptions of the sites as well as notes on production, exploration, and potential resources are included in this report. The appendix contains references to reported occurrences of tantalian and niobian minerals in Virginia.
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