A refractory product with periclase as the main mineral component. According to the different composition of raw materials, it can be divided into: magnesium brick made of brick magnesia, magnesium alumino brick added with a small amount of special grade alumina or industrial alumina, magnesia carbon brick added with a certain amount of graphite powder, with poor quality. Magnesia-silica brick made of high-silica magnesia. Compared with other refractory bricks, magnesia bricks have higher refractoriness, up to 2000 °C, high load softening temperature, large high temperature mechanical strength, and good resistance to iron oxide and calcium oxide. The chemical attack properties of alkaline slag. However, the general thermal stability is poor.

The magnesium oxide content in the product is about 85%. An alkaline refractory material having an alumina content of 5% to 10%, a periclite-based crystal phase, and a magnesium-aluminum spinel as a sub-crystalline phase (as a main binder phase). The apparent porosity is generally 15 to 18%. The coefficient of thermal expansion is 10.6 x 10-6 / °C. The thermal shock resistance is better than the corresponding magnesia brick. Since the matrix has a high melting point of magnesium aluminate spinel, the high temperature strength is higher, and the load softening start temperature is above 1580 °C. The slag resistance is also good. Generally, high-quality sintered magnesia is used as a granular material, and a fine powder composed of magnesia or bauxite clinker or industrial alumina mixed with a certain proportion is added, and is obtained by kneading, molding and firing.