Explanation

It is an organic gems materials produced in mollusks of mollusks and pearl mussels and formed by secretion. It is mainly composed of calcium carbonate minerals (mainly aragonite and caldte) and contains organic matter. The chemical composition is mainly composed of calcium carbonate (82% -86%), followed by crustaceous matter (10% -14%) and water (2% -4%). It has a concentric ring structure and can be divided into nucleated and non nucleated types. Nucleated cultured pearls have larger nuclei than natural pearls. The surface is delicate and clean, with strong luster, and the pickled hole that can clearly illuminate people is a high-quality bead. According to color, it can be divided into white series, red series, yellow series, black series, and others. The yield of rose and pink conch is very low. Mohs hardness 2.5-4.5. Foaming in case of acid, browning after combustion due to overheating, and sand feeling on surface friction. The quality of pearl is mainly evaluated from the aspects of size, luster, shape, color and surface quality.

Classification