Refractory clay is divided into four types: soft clay, semi-soft clay, hard clay and high alumina clay according to plasticity, mineral characteristics and industrial use. Soft clay is generally soil-like, easy to disperse in water, and can form plastic mud after mixing with liquid; semi-soft clay has poor dispersibility, and its dispersing part can also form plastic mud after mixing with liquid group. This kind of clay is often used as a binder when making refractory products. Hard clay is often in the form of block or plate, generally does not disperse in water, and has high refractoriness. It is the main raw material for refractory products. High alumina clay has high content of AL2O3, high hardness and specific gravity, and high refractoriness. It is often used to manufacture high-grade clay products.

Refractory clay is mainly used in the metallurgical industry as a raw material for the production of shaped refractories (bricks of various specifications) and unshaped refractories, accounting for about 70% of all refractories. The hard clay in refractory clay is used to make blast furnace refractories, ironmaking furnaces, hot blast stoves, lining bricks for ladles, and plug bricks. High-alumina clay is used to make electric furnaces, aluminum bricks for furnaces, high-alumina lining bricks and high-alumina refractory mud. Hard sticky bricks and high alumina clay are often used for calcining clinker at high temperature (1400 ~ 1800°C).