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Cultured pearl farming relies on a delicate biological process: technicians insert a small irritant, often a bead of mother-of-pearl, into an oyster, prompting the animal to secrete layers of nacre around it over several years. Not every oyster survives the procedure, and even among survivors, only a fraction produce pearls of gem quality, since factors like water temperature, nutrient levels, and the oyster's own health all influence the nacre's thickness and luster. This unpredictability means farmers typically seed thousands of oysters to yield a comparatively small number of high-value pearls. Despite decades of refinement, farmers still cannot fully control which oysters will produce fine pearls, making quality assessment only possible after the lengthy growing period ends.