Abstract
This study presents a mineralogical and geochemical investigation of rare earth elements (REE) in leached core samples from a uranium deposit in Kazakhstan. A total of 31 samples were collected from ore-bearing, sub-ore, and barren intervals of boreholes. The analytical workflow included gravity concentration (panning), heavy liquid separation, magnetic separation, and a combination of mineralogical, immersion, microchemical, luminescence, and electron microprobe analyses. The core material is predominantly composed of clay-rich sediments with quartz interlayers and sulfide mineralization (pyrite, marcasite), along with uranium-bearing phases. The heavy fraction contains minerals capable of hosting REE, including monazite, titanite (sphene), and garnet. Monazite, identified in all samples as sparse and isolated grains, represents the principal REE-bearing phase, although its abundance is generally low (<0.01 g). Additional associated minerals include Nb–Ta phases, scheelite, and accessory minerals such as zircon, rutile, apatite, and anatase. The results indicate the presence of REE mineralization within the leached core material and suggest its potential relevance for further geochemical assessment.