The main symbiotic minerals of cassiterite are biotite, pyrrhotite, pyrite, etc., and rhodochrosite, serpentine, etc., are also symbiotic with it, and secondly, it is also symbiotic with dolomite and magnesite. Since tin minerals are often associated with other metal minerals, many free metal ions are often produced in the ore by other mechanical actions such as crushing, grinding, and mineral dissolution. The flotation pulp usually contains other metal ions, such as iron, copper, calcium, lead, magnesium, etc. The physical and chemical effects of these metal ions on the surface of tin minerals have a greater impact on the flotation of tin minerals.

• Iron ions play a very important role in the process of tin flotation. During the flotation process of tin minerals, iron ions will destroy the film on the surface of tin minerals, causing the surface of tin minerals to be oxidized, thus making the flotation of tin ores difficult.
• Copper ions can form water-insoluble copper-tin salts with tin on the surface of tin ore and can inhibit the process of tin flotation through electrostatic interaction.
• Calcium ion is a vital metal ion in tin flotation. When calcium ions enter the tin ore, they will form water-insoluble calcium salts with tin, affecting tin ore flotation.

In actual production, the mineral composition of tin ore is complex, and many kinds of metal ions significantly impact the recovery of tin ore. According to the mineral composition of the tin ore, we should select the appropriate combination of agents through the beneficiation test in a targeted manner to reduce the impact of metal ions on the recovery of tin ore.