The distinction of natural from cultured pearls traditionally has been based on X-radiography. X-ray computed microtomography (μ-CT) has recently been applied to gain more insight into pearl structures. Using this technique, this article presents features observed in a selection of natural pearls and beaded and non-beaded cultured pearls. Based on these observations, μ-CT is shown to be a powerful tool for pearl identification.
Supplementary Videos (see below)
Two natural pearls, samples mxt 3 (freshwater; a) and mxt9 (saltwater; b); for details and explanation, see table 1 and figure 3.
A beaded cultured pearl, sample mxt 14b (saltwater); for details and explanation, see table 1 and figure 4.
Two non-beaded cultured pearls, samples mxt 1 (freshwater; a) and mxt 61_14 (saltwater; b). Also included is a short movie showing the rendered model of the cavity structure (“moustache”) in the center of sample mxt 1 (c); for details and explanation, see table 1 and figures 5 and 6.
A non-beaded cultured pearl with a complex structure, sample mxt 21_1 (saltwater); for details and explanation, see table 1 and figure 8.