Agata Duczmal-Czernikiewicz

Rare earth elements deposited in ion-adsorption clay-type deposits in Northern Kazakhstan were recognised using mineralogical and geochemical methods. The diversity and mineralogical properties of the Shok-Karagay deposit and Syrymbet ore fields under investigation in this study are closely related to the process of the formation of the deposits as well as the deposits’ architecture. A combination of mineralogical research and digital technology (GIS) was used to characterise the deposits. Rare earth elements from the cerium series were found in the following quantities: La (in ppm), 43–200; Ce, 57–206; Sm, 100–300; Eu, 22–100. Yttrium-series elements were found in the following quantities: Y, 31–106; Gd, 100–200; Tb, 100–200; Dy, 0–300; Ho, 0–20; Er, 0–364; Tm, 0.28–0.85; Yb, 2.2–39; Lu, 0–200. The wireframe and block models indicated that the bodies’ forms were 1800 m wide, 3500 m long, and 20–40 m thick. The major REE group minerals in both bodies were monazite and xenotime, whereas the minor minerals included yttrium parisite, silicorabdophanite, thorite, and orangite; moreover, ilmenite and titanomagnetite were found. The 3D models that were constructed indicated that the mineralogy and geochemistry of the ore bodies played a determining role in the deposits’ architecture.