Figure 3. UV-visible reflectance spectra of the darker gray nacre areas of all three P. mazatlanica shell samples shown in figure 2 are similar to the spectrum from a P. margaritifera pearl. All show a uroporphyrin feature at 405 nm and a feature at 700 nm, which is diagnostic of P. margaritifera. These spectra prove the similar spectral characteristics between P. mazatlanica and P. margaritifera.
Figure 2. The lip area of one P. mazatlanica shell was cut into three pieces to investigate the reflectance spectral characteristics in the dark and light nacreous areas. Photo by Lhapsin Nillapat.
Figure 1. These Pinctada mazatlanica shells were obtained from Mexico. Left: The shell has a rounded outline, with a nearly equal height and width. The exterior surface exhibits alternating yellowish brown and dark greenish gray colors, with whitish blotches fanning out from the center. Right: The interior view of the shell on the left alongside a smaller example showing a yellowish green nacreous rim with a distinct orient. Photos by Lhapsin Nillapat.
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