Citation: Zimanovskaya, N.A.; Oitseva, T.A.; Khromykh,S.V.; Travin, A.V.; Bissatova, A.Y.; Annikova,I.Y.; Aitbayeva, S.S. Geology, Mineralogy, and Age of Li-Bearing Pegmatites: Case Study of Tochka Deposit (East Kazakhstan). Minerals 2022, 12, 1478. https://doi.org/10.3390/min12121478 Academic Editors: Yunsheng Ren and Qun Yang Received: 6 November 2022 Accepted: 19 November 2022 Published: 22 November 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). minerals Article Geology, Mineralogy, and Age of Li-Bearing Pegmatites: Case Study of Tochka Deposit (East Kazakhstan) Natalya A. Zimanovskaya 1 , Tatyana A. Oitseva 1,2, * , Sergey V. Khromykh 3 , Alexey V. Travin 3 , Ainel Y. Bissatova 1,2 , Irina Yu. Annikova 3 and Saltanat S. Aitbayeva 1 1 Faculty of Earth Sciences, D. Serikbayev East Kazakhstan Technical University, 19, Serikbayev str., Ust-Kamenogorsk 070000, Kazakhstan 2 Geos LLP, 83, Protozanov str., Ust-Kamenogorsk 070000, Kazakhstan 3 V.S. Sobolev Institute of Geology and Mineralogy Siberian Branch of the Russian Academy of Sciences, 3 Koptyug ave., 630090 Novosibirsk, Russia * Correspondence: tatiana.oitseva@gmail.com; Tel.: +7-705-150-76-53 Abstract: New geological, mineralogical, geochemical, and geochronological data have been obtained for Li-bearing pegmatites from the Tochka deposit located within the Karagoin–Saryozek zone in East Kazakhstan. Earlier, the exploration works in this zone were carried out to detect only Ta and Sn mineralization, but other ores (including Li) were not considered. The estimation of lithium resources in pegmatites from the area was methodologically imperfect. Previously, it was believed that the formation of rare-metal pegmatite veins was associated with Late Carboniferous Na-granites. The obtained geological observation confirms that the ore-bearing rare-metal pegmatites at the Tochka deposits cut the Late Carboniferous Na-granites and do not cut the Early Permian Kalba granites. The associations of the accessory minerals in host hornfels, Na-granites, and rare-metal pegmatites are different and the accessory minerals in pegmatites are similar to the accessory minerals in the Kalba granites. Geochemical data show that the behavior of rare elements (Ba, Th, HFSE, and REE) and the levels of accumulation of rare metals prove that pegmatites are similar to the product of the differentiation of the granitic magmas of the Kalba complex. The 40 Ar/ 39 Ar muscovite age of the Tochka pegmatites (~292 Ma) fits the age range of the Kalba granite complex. Based on the main principles of the generation of rare-metal pegmatites, the Tochka pegmatites formed during the fluid–magmatic fractionation of magma in large granitic reservoirs of the Kalba complex. The Karagoin–Saryozek zone—located between several large granite massifs of the Kalba complex where host rocks play a role as a roof—may be very promising for rare-metal pegmatite mineralization. Keywords: rare-metal pegmatite; granite; lithium resources; development of Li pegmatite deposits; Ar-Ar dating; East Kazakhstan 1. Introduction The Central Asian Orogenic Belt (also known as the Altaids) accommodates volumi- nous Phanerozoic granitoid batholiths [1–9]. Granitic magmatism hosts Rb, Be, Mo, and W metals [10–13], including especially valuable Li, Cs, Ta, Nb, and Sn. Many rare-metal pegmatite bodies (first of all the lithium–cesium–tantalum (LCT) pegmatite family) are spa- tially and genetically associated with large granitoid intrusions and often occur as fields or swarms of veins, commonly along the margins or above the roofs of plutons [11,12,14–17]. Rare-metal pegmatite mineralization (LCT family) related to granitic magmatism is abundant in East Kazakhstan, which is part of a Late Paleozoic collisional suture between Siberia and Kazakhstan [18,19]. Magmatic activity in the region was the most active in the Early Permian [20–22] and produced, among others, the large Kalba and Zharma granitoid batholiths [21,22]. Large-scale magmatism occurred in a setting of post-collisional extension and was maintained by heat from the Tarim plume [23–27]. The area—with multiple and diverse juxtaposed igneous complexes—stores extremely rich resources of base, noble, Minerals 2022, 12, 1478. https://doi.org/10.3390/min12121478 https://www.mdpi.com/journal/minerals