22 Large Lustrous Silver-White Flat Diamond Pearls - 15mmPrice is 15 1 2 inch string of these beautiful pearls. Each measures 15mm x 15mm x 6mm thick, drilled as in picture about 22 to the string. 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, the mollusk coats the intruder with the same