We examine crystallization conditions for saturated brines of calcium, potassium, and magnesium chlorides from the Angara‑Lena artesian basin, Siberian Platform. The study focuses on temperatures matching actual thermal conditions in wells of the “Lithium” site at the Kovykta gas‑condensate field. This critical type of lithium‑bearing raw material is classified as hard-to-recover reserves. In most wells (depths to 2.2 km), rock temperatures in the upper geological section remain below 20 °C. During well operation, various salts precipitate from saturated magnesium-calcium chloride brines within the production line. This leads to rapid wellbore clogging and eventual production shutdown. Thermodynamic analysis of phase diagrams reveals that crystallization yields antarcticite CaCl₂·6H₂O, tachhydrite Mg₂CaCl₆·12H₂O, minor amounts of carnallite KMgCl₃·6H₂O, bischofite MgCl₂·6H₂O, and several other chlorides, depending on temperature. At temperatures above 55 °C, salt precipitation becomes negligible. Thermohydrodynamic simulations of a single flowing well under hydrogeological conditions similar to those at the Kovykta area (southern Siberian Platform) demonstrate the feasibility of long-term (1 month to 1 year) exploitation of saturated sodium-chloride and calcium-chloride lithium-bearing brines. Such operations can yield lithium production rates of 31.2 to 4.2 t per well.