The leaching of Elliot Lake ore by nitric acid was investigated as an alternative means of extracting uranium. The rate of growth and the nature of radium-bearing sediments from the leach liquor were studied by examination of filtered sediment with scanning electron microscopy. The sediment was found to contain elemental sulfur and Fe- and Si-containing precipitates, and to contain as much as 68% of the radium after aging 2 days at 5°C. Coprecipitation with natural barites or with BaSO4precipitated about 95% of the radium, leaving a leach liquor containing <20pCi/l of radium.