Luster- the Substance of Pearl Beauty
The luster is the reflection, pearls get their unique beauty from the light reflecting through layers of fine crystalline nacre slowly but surely deposited by an oyster. Just about transparent nacre gives the deepest luster and the largest reflection. A high-quality pearl will have a brilliant even reflection with a fine warm glow or radiance. Lower quality Pear Necklace Jewelry have a dull sheen.
High quality Akoya saltwater pearls have a higher luster than South Sea or Tahitian pearls, which have a tendency to have a softer, more diffuse reflection.