Pearl is regarded one of the most sought after jewelry. It can be created in various types of shelled mollusk, such as conch shell, mussel, abalone, and oyster. Yet, only pearl oyster and pearl mussel can create jewelry-grade pearl.
Pearl is formed inside the shell of mollusk. Its formation process is similar to how our eyes produce tears to wash out irritants when our eyes come into contact with them. When irritants, such as grain of sand or rocks, enter the shell, the mollusk, being irritated, will secrete nacre to coat the irritants.
Generally, pearl can be classified into two types:
- Saltwater pearl
- Freshwater pearl