The magnetic iron-ore prospects of the Llano region of central Texas were investigated in a program which combined dip-needle and gravity-meter surveys by the Bureau of Economic Geology of The University of Texas and the U.S. Geological Survey with exploration by the U.S. Bureau of Mines. Magnetic observations were made on the Iron Mountain, the Bader, the Gamble, and the Olive mine prospects. Gravity observations were made over the first three areas, which subsequently were drilled. Approximately 65,000 long tons of ore is indicated for the Iron Mountain deposit. The investigations indicate the applicability of combined dip-needle and gravity-meter surveys in search of magnetic iron-ore deposits.