... Alkali metal chloride0.90%max1.30% Metallurgical industry: to manufacturing refractory materials and build ... smelting magnesium metal materials. . Chemical industry: mainly used for production of magnesium salt, such as magnesium oxide, magnesium hydroxide, magnesium carbonate, ... board, magnesium the manhole covers, bath crock, door window frame houses and activities. . Machinery industry: life, ...