Large 9mm Cherry Red Pearl StringPrice is for per 15 inch string of these unusual large 9mm pearls. Ideal for reselling or stringing. Note: as with all pearls, 9mm is the largest in the string, approx half are only 8mm. The least expensive cultured pearls today rival the most expensive natural pearls ever found. Natural freshwater pearls occur in mussels for the same reason saltwater pearls occur in oysters. Foreign material inside a mussel can't be expelled. To reduce irritation,