A Pearls Luster

Luster serves as a crucial aspect for consumers to gauge pearl quality, as it can be easily assessed with the naked eye, unlike nacre quality which requires expertise. Pearls boasting high luster exhibit a mirror-like reflection, accompanied by a three-dimensional glow and subtle display of Orient—varied surface colors—while those with low luster appear dull and lifeless.

The intensity of luster results from the reflection and refraction of light passing through layers of aragonite, influenced by both the quantity of crystals and their specific geometric arrangement secreted by the mollusk. Factors such as the oyster’s health, water temperature, and nutrient levels significantly impact nacre secretion, thereby affecting the pearl’s luster.

While intense luster often indicates thick nacre and thus enhanced durability, this correlation isn’t always straightforward. Some cultured pearls may possess thick nacre yet lackluster due to poor density, highlighting the complex interplay of factors influencing pearl quality.