Natural pearls are rare and expensive. They look the same as cultured pearls, the only difference is that they were grown cultivated in a wild oyster. Cultured pearls are made by implanting a piece of sand in an oyster and waiting for the pearl to grow. The majority of bought pearls are cultured. These look identical to natural pearls, but are man-made.
Freshwater pearls can be round, but these are more expensive than their baroque counterparts. Both freshwater and saltwater are available in nearly any color.
Always examine a pearl’s color against a white backdrop, such as a piece of white velvet or a similarly glare-free fabric. Use diffused full-spectrum light when examining the pearl’s color. If you’re buying a strand of pearls, always examine the colors of each of the pearls in contrast to the ones next to it.
Luster is easy to examine in a round pearl, while it is more difficult to examine in a baroque pearl because of the many contours. Check the whole pearl to make sure the luster is the same the whole way around.
Round: perfectly spherical with no surface blemishes. Off-round: slightly wider on one side of the pearl, but not elliptical. Off-round pearls can be easily passed off as round pearls in a strand. Oval: rounded with a significant difference between the length and the width. A step further than an off-round pearl. Drop: egg-shaped with one end that’s rounded, and one end that’s slightly pointed. Button: a mostly round pearl, with one or two asymmetrical curves. Mabe: a round pearl that is flat on one side, creating a half circle. Baroque: a ‘natural’ pearl with lots of lumps and asymmetrical curves.
Pearls grown in clams and conches are non-nacreous.
The exception to this rule is a strand of baroque pearls; pay attention to color and luster, rather than shape.
