Pearl has a hardness of 3. The price of pearls vary widely as a result of luster, size, how they were grown, color and type. Natural pearls are the most expensive, followed by cultured pearls. Fresh water pearls tend to be relatively inexpensive. Some say rubbing a pearl against their teeth can determine whether a pearl is real or fake since fake ones will feel too smooth.
Pearls are less durable than most gems.
They are sensitive to acids, dryness, and humidity. When taking off your pearls, wipe them with a dry, lint-free cloth. If needed, clean your pearls with warm soapy water being very careful to not get water into the drill hole as the pearl may discolor. Always store your pearl necklaces flat as the silk will stretch. Store pearls separately from other jewelry as they will scratch.