The tin-spodumene belt lies mostly in North Carolina betweeen Lincolnton and the State line. Cassiterite occurs sparsely in hundreds of spodumene-bearing pegmatite bodies, which were emplaced in joints where the rocks are uniformly competent, and parallel to the layering where competent and incompetent rocks are interlayered. Locally, cassiterite is sufficiently abundant in the pegmatite bodies and in closely associated greisen (quartz-muscovite rock) to be of possible commercial value. There are at least 91 such deposits of potential tin ore in North Carolina, and 1 near Gaffney in South Carolina. Includes 4 plates. By T.L. Kesler, 1942. 25 pages.