The jewelry factory stated that pearls can be divided into natural pearls and cultured pearls, while cultured pearls can also be divided into sea pearls and negotiation pearls. The production of natural pearls is small and expensive; Cultivating pearls can yield a large amount, so the price is much lower. The main difference between the two lies in the core, which is usually composed of fine sand or sparganum, or even without a core. The core of cultured pearls is a relatively large artificial pearl, so the outer capsule layer is relatively thin. Mainly manifested on the epidermis, natural pearls have poor concentricity in their appearance design due to their random growth conditions and minimal turnover of dirt in the nucleus.

The inner core of cultured pearls is round, so the concentricity is good after being formed into pearls. Natural pearls grow for a long time, resulting in a delicate material, a strong layer, a smooth outer skin, very few "bumps", and are more fully transparent. Cultivated pearls have a thin layer, less smooth material, and a "wax" like glossiness due to their short sound when formed. The surface usually has some convex and concave "hot bubbles", and the clarity is also weak. If it is a broken pearl, carefully observe the hole with a high-power magnifying glass. If it is a cultured pearl, a dark brown boundary can generally be seen inside the pearl, which is also the boundary between the inner core and the pearl layer that grows afterwards.

The imitations of pearls include plastic imitations of pearls, glass imitations of pearls, pearl shells imitations of pearls, and laminated pearls. Pure natural pearls gently rub with teeth, giving a textured feel. Plastic imitation pearls look too bright at first, but upon closer inspection, their colors are monotonous and rigid, with uniform sizes, light touch, and a warm feeling. There are dents on the punched holes, and visible beads can be picked with a needle. The difference between pearl like shellfish and pearl like shellfish is that when they grow larger, they cannot see the unique growth patterns of pearls, but instead have a monotonous rough surface similar to the surface of an egg shell.