Why are high-intensity magnetic separators needed for limonite and siderite ores?

In mineral processing, magnetic separation relies on the varying degrees of attraction minerals exhibit when exposed to a magnetic field. While strongly magnetic minerals like magnetite can be effectively captured using low-intensity separators, other iron-bearing minerals require more powerful equipment.1

High-intensity magnetic separators are necessary for limonite and siderite because these minerals possess lower magnetic susceptibility compared to strongly magnetic ores. Because they are not as easily magnetized, a stronger applied magnetic field is required to exert sufficient force to separate them from gangue minerals. These high-intensity devices are also utilized for processing other weakly magnetic materials, including iron-bearing manganese, titanium, and tungsten ores, as well as certain iron-bearing silicates.12