2. Jadeite is mainly composed of jadeite minerals or other sodalite with high molecular weight, also known as sodalite, accompanied by a small amount of other minerals such as pyroxene, amphibole and albite. Composition: NaAl(Si2O6). English: Emerald. The hardness is 6.5~7, the specific gravity is about 3.33 and the refractive index is 1.66.

3. The refractive index is the ratio of the propagation speed of light in a vacuum environment to that in a certain medium. Refractive index is one of the most stable properties of gems, and each kind of jewelry and jade will have a relatively fixed refractive index value, which is an important parameter to determine the types of jewelry and jade. Usually, when we identify a piece of jewelry and jade, we will first measure its refractive index with a refractometer to see what jade this refractive index corresponds to, and then combine its other gemological characteristics to determine its type.