Take a peek at the lustrous history of these gems from the deep. Almost all salt water pearls are cultured, while fresh water pearls are readily available au natural. If it weren't for the advent of cultured pearls, there would virtually be no pearl market today.
Pearls are available in more colors than even sapphires.
Not all round pearls are round. They are classified as round, slightly off round and off round. Nacre is the lustrous protective coating oysters produce over intruding irritants. Pearls are measured by size, not weight. Uniformity of size is the most important factor in strands.