The common defects of the pearl surface are: the waist line (thread), the sag (flat head), the needle point, the scratch and so on. Pearls are bred in the lake and sea by the bivalve shellfish. The pearl is influenced by the environment during the growth of the Pearl, and there will be many imprints of nature.
As the saying goes, "no blemishes, no pearls", there are no 100% flawless pearls. Even if the surface is flawless pearls, such as using magnifying glass, we will see that the surface of the pearl is characterized by sand dunes.
Generally speaking, the blemish is seen by the naked eye, and it is about 0.5 meters away to see the defects as acceptable standards. It is not recommended that you pursue the perfection of absolutism. We must have a correct understanding of the meaning of "flawless" level. From an aesthetic point of view, fine flaws will not affect the overall impression and social image of pearls. As the saying goes, "the", say that we treat the beauty of philosophy.
Introduction of defects on the surface of pearls
The surface of the Pearl will deviate from the ideal state, there are many defects, such as grooves and convex, spots, bubbles, cracks, pits, ridge, black tip gap, etc.. If the temperature and ion concentration of the water change little, the crystal growth is stable, the structure is clear, the surface of pearl is smoother, otherwise, the crystal is easy to mutate and produce defects.
100%, perfect flawless pearls do not exist in theory, because even if the naked eye is hard to see, with the help of 10 times or even higher magnifying glass, we can see that the surface of pearl is like the texture and uneven of the lunar surface.