Pearls are composed of about 2 to 4 % water along with calcium carbonate and an organic binder called conchiolin. If the pearls become dehydrated, they can get brittle and crack. Consequently, they should not be kept near heaters or in places that get strong sunlight, such as on a window sill. Safe deposit boxes can be unusually dry, so if you ever store pearls there, try to take them out occasionally and expose them to humidity or moisture. Sealed plastic bags are not the best place for pearls. They can keep them from breathing and getting moisture.

Since pearls are soft, they should be kept in something that will protect them from scratches. Jewelry pouches or cloth bags are ideal. Pearls can also be wrapped in soft material and kept wherever convenient. Jewelry boxes may be handy, but they are also the first place burglars look.