PRELIMINARY FINDINGS OF THE HEAVY MINERALS IN KAOLIN AND BAUXITE, UPPER COASTAL PLAIN, GEORGIA

Significant amounts of the rare earth elements (Sc, Y, La-Lu) and other critical minerals (Ti, Zr) were found in the heavy mineral fractions of kaolin mine waste and kaolin ore. REE (up to 0.5 wt. %) were typically found in zircon and REE phosphate minerals (monazite and xenotime) in the heavy mineral fraction of kaolin mine waste in the Buffalo Creek kaolin is from central Georgia. The types of heavy minerals differed between bauxite-kaolin deposits and the mined kaolins in central Georgia. The heavy fractions of mined kaolin contained considerable amounts of rutile, zircon, anatase, muscovite, trace xenotime, and Fe-oxides. The heavy mineral fractions of the bauxite-kaolin samples were more variable. The heavy mineral fractions of the bauxite-kaolin samples were composed of more weathered pyrite, Fe-oxides, and muscovite. Gibbsite, and trace possible amounts of monazite, quartz, xenotime were also observed in the heavy mineral subfractions of the bauxite-kaolin samples. The presence of weathered Fe-oxides and pyrite, and the lower rutile contents was the most significant difference between the bauxite-kaolin and the heavy fractions of mined kaolin. The bauxite zones in the bauxite-kaolin deposits were highly weathered as indicated by the larger presence of gibbsite per whole rock mineralogy. Conversely, gibbsite was absent within the enclosing kaolin layers (e.g. Upper and Lower Kaolin units) of the bauxite-kaolin ore bodies, and gibbsite was also absent from the mined kaolin ore which lacked bauxite zones entirely. The higher total REE within the Lower Kaolin unit beneath the bauxite zone hosted within the bauxite-kaolin deposit type showed no significant difference in P on whole rock basis. The result was an unexpected result given the strong relationship between REE-bearing phosphate mineral and total REE as shown by the kaolin deposits types that lack bauxite zones.