In addition to fluorite, apatite, phosphorite, fluorine is most often associated with tin ore deposits. According to I.G. Magakyan, tin-bearing hydrothermal solutions carry tin in the form of SnF₄, and increased fluorine content in the rock and the presence of fluorine-bearing minerals are a search sign. According to the study of tin deposits in the Far East, tin is transported by hydrothermal solutions in the form of Na₂[Sn(OH,F)₆] compounds. These tin deposits are characterized by the presence of fluorite and increased fluorine content in chlorite and sericite. This was the prerequisite for studying the possibility of using fluorine as one of the indicators in hydrochemical searches for tin ore deposits. Most researchers studied fluorine content in water mainly from the position of biological impact of water on humans (dental caries, dental fluorosis). They noted fluoride deficiency in landscapes with humid climates and relative excess in dry, climates and in areas of modern and ancient volcanism.