What type of pearls do mollusks typically produce when they live in cooler waters?

Mollusks that live in cooler waters typically produce pearls with higher luster due to the slower growth rates associated with these environments. The process of nacre deposition—the layering of aragonite and conchiolin that forms a pearl—occurs more gradually, allowing for the formation of a thicker, more reflective nacre layer. This results in a brighter appearance and greater optical quality. Higher luster is often desired in the market, as it enhances the pearl’s visual appeal and can indicate better overall quality.

The characteristics of cooler water, such as reduced metabolic rates in mollusks, contribute to the formation of these premium pearls. Warmer waters often yield quicker growth, which can lead to different pearl qualities. Therefore, the production of pearls in cooler environments is most commonly associated with those that exhibit superior luster.