9403194 Hughes This award provides 50 % of the funding necessary to acquire a new x-ray powder diffractometer that will be installed and operated in the Department of Geology at Miami University (Ohio). The University is committed to providing the remaining 50% of the cost of acquiring this instrument system. The new x-ray powder diffractometer will replace an outmoded 1970 instrument and will be the only such instrument on the Miami campus. The diffractometer system will be used in research projects that include : 1) structural studies of minerals, 2) studies of disorder in intermetallic alloys and their hydrides, 3) studies of minerals in the low-temperature weathering environment, 4) studies of the source and transport of carbonate sediments , and 5) investigations of clay minerals related to their use in potassium-argon and rubidium-strontium dating methods. The diffractometer will also be used in graduate and undergraduate teaching. ***