**6. Classification of pearls**

Pearls can be broadly classified into 3 different types (**Figure 3**). They are as follows-

#### **6.1 Natural pearls**

These pearls form naturally in the environment when mussels ingest a foreign particle without the need for human involvement. Natural pearls have a small core or nucleus with thicker crystalline pearl nacre. It has an uneven shape and is quite small. Due to the margins of the overlaying aragonite crystals, the surface of natural pearl has a rough texture.
