Pearl, "Jane" is precious, and "pearl" is a sphere. Together, they are called pearls. Pearls are produced in some mollusks, such as white butterflies and spider mother-shells. Shells are bead-like particles produced by foreign bodies infiltrating into their shells (becoming irritants), and they are "pearl embryos". As time goes by, this kind of pearl will become bigger and bigger because of the package of mussel shell secretion. It can be said that the bigger the mussel, the bigger the pearl, so there is a saying that "old mussels give birth to pearls".

Pearl is an organic gem. "Organic matter" is "organic matter". In the past, it generally refers to the compounds that constitute animals and plants, and it is believed that only animals and plants can produce them; Now it refers to the general term for carbonaceous materials. There are many kinds of organic compounds. As far as gems are concerned, there are pearls, amber, coral, ivory, coal essence and so on.

Pearls are measured by particles.

1 size = 0.0648g. The value of pearls depends on their size, roundness, color, luster and shape. In other words, the bigger the better, the rounder the better, black is the most precious, and smooth is the top grade. However, the evaluation of pearls is more complicated, and there is also a collocation problem.

Judging from the world pearl market, there is a saying that "East Pearl is not as good as West Pearl, and West Pearl is not as good as South Pearl". Dongzhu refers to Japan, while Zhu Xi refers to Western Europe. Nanzhu is a pearl produced in Hepu County, Guangxi, China. Nanzhu granules are round, pure in texture and bright in color; Among them, "Night Pearl" and "Turntable Pearl" are the most precious.