Why is flotation especially useful for fine-grained minerals?

Flotation is the most widely used method for concentrating fine-grained minerals because it overcomes the limitations of traditional separation techniques, such as gravity, magnetic, or electric methods, which struggle to process very small particles.12

Historically, these fine particles were often lost as waste in gravity concentration plants. Flotation solves this by exploiting the physicochemical surface properties of minerals rather than their size or density. By using chemical reagents to alter the wettability of specific mineral surfaces, processors can make valuable particles hydrophobic (water-repelling). These particles then adhere to air bubbles and rise to the surface as a froth, allowing for efficient separation from hydrophilic (water-attracting) gangue minerals.21

This process is particularly valuable for complex, intergrown ores containing metals like copper, lead, and zinc, which are difficult to separate by other means. By enabling the precise modification of surface properties, flotation allows for the recovery of minerals that were previously considered too fine or complex to process economically.12