A method for the preparation of high-density Th02 of the ' correct particle size for vibratory compaction is under development. The method being developed appears easily adaptable to remote operation. Pure ThO£ made by this method was readily compacted to 86$ of theoretical density by pneumatic vibration. Preparations of high-density mixed TbX^-UOg and UO2 by this general method have been successfully carried out. Densification of arc-fused mixed oxide by a pneumatic vibrator compared favorably with results of tests with the same oxide using electronic vibrators at both Huntsville, Alabama, and Savannah River. In the limited tests with the electronic vibrators at the other sites, it appeared that a saw-tooth wave shape gave greater densification than a sine wave or random noise. LEGAL NOTICE-I This report was prepared as an account of Government sponsored work Neither the United States, nor the Commission, nor any person acting on behalf of the Commission A Makes any warranty or representation, expressed or implied with respect to the accuracy completeness, or usefulness of the information contained In this report, or that the use of any Information, apparatus, method or process disclosed In this report may not infringe privately owned rights, or B Assumes any liabilities with respect to the use of, or for damages resulting from the use of any information, apparatus, method, or process disclosed in this report Ae used in the above, "person acting on behalf of the Commission" Includes any employee or contractor of the Commission, or employee of such contractor, to the extent that such employee or contractor of the Commission, or employee of such contractor prepares, disseminates, or provides access to, any information pursuant to his employment or contract with the Commission, or his employment with such contractor NOTICE This document contains information of a preliminary nature and was prepared primarily for internal use at the Oak Ridge National Laboratory. It is subject to revision or correction and therefore does not represent a final report. The information is not to be abstracted, reprinted or otherwise given public dissemination without the approval of the ORNL patent branch, Legal and Information Control Department.