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The by-products of the Far East Sn deposits related to Li–F granites include trace elements. The petrography and mineral composition of the Sn-bearing metasomatites of the Verkhneurmiysky ore cluster (VUOC) of the Amur region (feldspatites, greisens, zwitters, turmalinites, and chloritites) and the multistage complex rare-metal (RM) mineralization of the Sn occurrences in area of Li–F granites are studied. The minerals of strategic metals (Nb, Ta, W, Y, REE (from La to Lu), Be, Li, Rb, Zr, Hf, In, Sc, Se, Cd, and Te) are found. The RMs occur as minerals (fergusonite, plumbopyrochlore, allanite, monazite, roquesite, sakuraiite, etc.) and isomorphic substitution in the ore (wolframite; cassiterrite; Cu, Sn, Fe, Mo, Zn, and Pb sulfides; native bismuth; etc.) and rock-forming (fluorite, siderophyllite, muscovite, and epidote) minerals. Some RMs (Y, REEs, Nb, In, and Sc) most frequently occur in Sn-bearing metasomatites. The RM minerals formed during the VUOC evolution (from the premineral feldspatite to the postmineral chloritite stage) with decreasing intensity of RM mineral formation and compositional evolution from lithophile to chalcophile RMs: (LREE, Zr, Hf) → (W, Nb, Ta, Y, HREEs, Sc) → (Sn, In, Cd, Se, Te). The formation of the VUOC RM mineralization was caused by magmatic, metasomatic, and crystal chemical factors. The possible complex exploration of the Far East Sn deposits is shown for areas of Li–F granites. [ABSTRACT FROM AUTHOR]

The phenomenon of an abnormally high concentration of tantalum (5.3–17.9% of Ta2O5) in accessory cassiterite from lithium–fluoric granites of the Arga-Ynnakh-Khaysky massif in East Yakutia is described. The significant isomorphic capacity of the cassiterite structure in relation to the tapiolite impurity, which reaches 15.1–39.8%, is established. It is concluded that the origin of tantalum-bearing cassiterite is determined by the specific crystallization conditions of lithium–fluoric granites, and their wide distribution in the Far East of Russia requires further study of the typochemistry of accessory cassiterite from rare-metal granites and genetically related metasomatites. [ABSTRACT FROM AUTHOR]

The article presents a study on the zircon content of rare-metal lithium-fluorine granites in Far East. It says that cathodoluminescence (CL) and back-scatter detector (BSE) images show presence of porous outer and fractured rims and monolithic inner core. It says that the rims' compositional peculiarities were observed through secondary ion mass spectrometry and electron probe microanalysis. Results show that zircon composition from the granites were similar with hydrothermal zircon.

The article presents a study on the lutetium-hafnium (Lu-Hf) and uranium-lead (U-Pb) isotope systems with concepts of geochemical evolution of the crust of the Earth. It says that the study used zircon U-Pb dating for verification due to the material's low sensitivity to greisenization. It discusses the analysis of the age ranges between lithium-fluorine (Li-F) formation, which was characterized by monzonitoids intrusions. It adds that the data obtained show that Li-F granites from the Far East are the youngest in Eurasia.