Rosebud Conch Pearls Studied by GIA

Figure 1. “Rosebud” conch pearls of various pink tones ranging from 0.93 to 14.72 ct. Photo by Sood Oil (Judy) Chia.

Figure 1. “Rosebud” conch pearls of various pink tones ranging from 0.93 to 14.72 ct. Photo by Sood Oil (Judy) Chia.

In late 2016, GIA’s New York lab staff had the opportunity to study part of Susan Hendrickson’s conch pearl collection. Among the assortment of conch pearls of various sizes, colors, and shapes, a few “rosebud” specimens caught our attention (figure 1). The term “rosebud” is most commonly used to describe characteristically shaped freshwater nacreous pearls, but this is the first time GIA has examined conch pearls with such shapes (figure 2). The nine pink specimens had roundish outlines with a button-like appearance. But in keeping with the rosebud pearl form, they exhibited differences in the bumps or ridges on their surfaces. Some bumps were rounded and spread out, while others were jagged and tightly grouped. The authors could not locate any reports of rosebud conch pearls in the literature, and the cause of these distinctive surface structures is unknown. One possible explanation is that when a pearl forms in a pearl sac positioned in a region of muscular activity rather than the mantle, it will not form in a smooth symmetrical shape (E. Fritsch and E.B. Misiorowski, “The history and gemology of Queen conch ‘pearls’,” Winter 1987 G&G, pp. 208–221).


Read entire article here: https://www.gia.edu/gems-gemology/summer-2017-labnotes-natural-conch-rosebud-pearls?utm_source=education_facebook&utm_medium=social&utm_campaign=conchpearl

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