Rare earth elements and uranium prospect on weathered granitic rocks in Tanah Merah, West Kalimantan.

Rare Earth Elements (REE) and Uranium (U) are found in several locations in West Kalimantan. The presence of this strategic mineral becomes a fascinating object to study. Tanah Merah is a potential sector in West Kalimantan which contains uranium and rare earth metals. Geological mapping, mineralization observations, and sampling of uranium and rare earth elements bearing ore have been carried out by geological and geochemical mapping to determine the potential of the research area. Geologically, the source rock in the study area is meta-silt, quartzite, mica schist, and igneous rock composed of rhyolite, rhyodacite, and several weathered granite intrusions. Monazite and uraninite mineralization occurs as lenses, veins, and disseminated in weathered granite bodies. In the Tanah Merah area, uranium and REE carrier minerals are found in the form of uraninite and monazite. The characteristics of monazite as a uranium and REE-bearing minerals have the characteristics of monazite formed in granitic rocks (La+Ce+Pr>75 and Ce/(Y+Nd) >2. This monazite has a low thorium content compared to uranium. The presence of monazite is associated with biotite, epidote, tourmaline, apatite, rutile, ilmenite, tetrahedrite, pyrite, chalcopyrite, and arsenopyrite. Weathered granite in the study area shows that monazite was formed in orthomagmatic and pneumatolytic zones. [ABSTRACT FROM AUTHOR]