Shapes and sizes of fresh water pearls
The dimensions of cultured pearls are measured with precision gauges, capable to measure the diameter of a pearl in hundredths of millimeters.
Calibration is a fundamental step for the selection and classification of cultured pearls: the bigger the pearl, the higher its commercial value. To understand this mechanism, we need to consider that the size of cultured pearls is determined by a wealth of variables (climate, how long they stay underwater, the plankton’s nutritional quality, etc…). In any case, making a very large pearl is always difficult for the oyster, no matter the species.
Cultured pearls come in many shapes, divided for commercial reasons into regular shapes (spherical, semi-spherical, button, drop, oval) and irregular shapes (baroque and ringed). Shape is a very important factor for cultured pearls’ evaluation: the more symmetrical a pearl, the higher its value. The shape of cultured pearls is dictated by the randomness of nature, and only a certain percentage of the culture (different depending on the variety) will feature a perfectly spherical shape.
For salt water cultured pearls such as the Akoya, the Southern Sea or the Tahiti kind, the grafting of a round rigid nucleus favors the steady growth of the pearl, whereas for fresh water pearls without a nucleus, shapes tend to be more irregular. We present to you, below, the different shapes and sizes for fresh water pearls.
Spherical pearls with a perfectly round shape. Natural spherical pearls are very rare, whereas cultured pearls, and especially the Akoya ones, often possess a perfect roundness.
Semi-spherical. Near-round pearls or natural spherical pearls have a minimal diameter difference comprised between 2% and 5%. Often, semi-spherical pearls already mounted on a jewel appear to the spherical pearl observer.
Cultured button pearls, or natural buttoned and flattened pearls. They are mainly used for earrings and rings because they have no edges, hence are more discreet.
Cultured or natural drop-shaped pearls. Perfect pearls are highly sought-after and expensive, in the industry lingo they are called natural drop-shaped pearls, characterized by an elongated, not-too-flat shape.
Cultured or natural pearls that possess a shape similar to an egg, the upper part being symmetrical to the lower part. Oval pearls particularly proportioned are very popular.
Baroque cultured or natural pearls, of irregular and undefined shape. Generally, baroque pearls have lower prices and are used in the modelization of artistic jewelry, with imaginative and creative designs. They are also called Scaramazze pearls.
Cultured or natural pearls with a regular shape are characterized by highly visible or simply suggested rings. They are part of some of the cheapest pearls on the market, along with the baroque ones.