Potassium fertilizer is in short supply in China. However, there is a considerable resource of insoluble potassium resources in the soil mineral or potassium-baring low-degrade rocks. Most of these kinds of potassium exist in aluminous silicate minerals f However, there is a considerable resource of insoluble potassium resources in the soil mineral or potassium-baring low-degrade rocks. Most of these kinds of potassium exist in aluminous silicate minerals f