White or grayish or in the form of particles. The humidity sensitive. Easy to absorb carbon dioxide and moisture from the air. Soluble in aqueous calcium hydroxide and produce a lot of heat, dissolve in acid, glycerol and sucrose solution, almost insoluble in ethanol. The relative density of 3.32 ~ 3.35. The melting point of 2572 DEG C. Boiling point is 2850 ℃. Refractive index 1.838. Corrosive.

Used in the manufacture of calcium carbide, soda, bleaching powder, used as a building material, refractory material, desiccant and soil improvement agent and calcium; used as a flux, analysis reagent manufacturing fluorescent powder; also used in tanning, purification of waste water; used as a building material, metallurgical flux is the main raw material, calcium hydroxide and calcium compounds, but also the chemical industry in the cheap base.