Nacre Quality – A thicker nacre does not always guarantee that you will have a better pearl. However, in most instances thicker nacre will also tend to be a more lustrous pearl. If you look at your strand of pearls and they appear to be chalky they probably have thinner nacre. Also rotating your pearl and seeing blinking which is the pearl’s nucleolus showing through is also a sign of thin nacre. If you can look at the end of the pearl around the hole and it you see chipping that shows the bead it is a sign of thin nacre and will probably not be very durable. There are three classifications for nacre quality
Acceptable - The nucleus is not able to be noticed. You might see a very slight blink upon rotating it. The appearance is also not chalky.
Nucleus Visible – The pearl will blink, you will see a flicker of light to dark when rotating. You also see evidence of the bead through the nacre.
Chalky Appearance – The pearl has a whitish appearance and it is dull.