The shape of pearls is one of the most important criteria in choosing and valuing a pearl. Indeed, the shape allows for more or less harmonious assemblages with other stones and pearls. 

Types of pearls: fine and cultured

First, it is important to note that there are 2 types of natural pearls : fines And of culture, a criterion which will strongly influence the shape and value of a pearl.

• Fine pearls are formed without human intervention, in mollusks bivalves (oysters or gastropods), within the tissue intended to secrete the mother-of-pearl of the shell. The fine pearl was particularly honored during the Renaissance and the 19th century, notably the necklaces "falling" with a larger pearl in the center surrounded by pearls of decreasing size. In the late 19th and early 20th centuries, high demand led to an increase in prices.

• Cultured pearls require human intervention; there are two types.
  Saltwater cultured pearls, which are created froma small mother-of-pearl core and a piece of the mantle of a sacrificed oyster that are inserted into the oyster's reproductive organ (the gonad). Then, the pearl layers will cover this mother-of-pearl ball. This technique was invented in 1761, thanks to a Swedish naturalist, but it was in Japan that the technique was developed. Indeed, the Japanese, in particular Kokichi Mikimoto, around 1920, developed the culture of round pearls in seawater, which was an immediate success in France, even surpassing the commercial success of fine pearls.
  Later, appeared freshwater pearls, entirely formed from layers of mother-of-pearl (without core). Today, freshwater pearls are highly valued due to their lower cost, quality and availability. Indeed, theTheir production is cheaper, faster and China produces up to 1500 tonnes per year, a figure which has increased further following the change in the types of moulds used around the 1990s.

The different shapes of pearls

There are two categories of shapes: regular pearls with similar shapes and irregular pearls called “baroque”.

Regular pearls:

• Round pearls, spherical, the first choice. The rounder a pearl is, the fewer imperfections it has, the more its value will increase. 
• The symmetrical pearls, But no spherical: the flat round pearl also called “button”, the oval pearl, the pearl drops in the shape of a water drop….

Regular pearls are mostly used on necklaces And bracelets in full circle, where the search for symmetry and regularity is crucial.

Irregular pearls:

• The baroque pearl is completely irregular and not symmetrical; it therefore has a unique value of its own. There are a multitude of pearls classified in the “baroque” category: the circled pearl, approximately round or oval, which has lines on its surface, the keishi pearl flat and irregular as well as the mabé pearl hemispherical in shape: rounded on one side and completely flat on the other, used for making earrings and rings because it adapts wonderfully.
• The semi-baroque pearl, which has a baroque - irregular - part, but also a round - regular - part. However, semi-baroque pearls are for the sake of simplicity often classified in the pearl category "baroque”.

Irregular pearls are mainly used as pendants especially on earrings or hanging from chain necklaces, but also asymmetrical rings.

What influences the shape of a pearl during its creation?

As previously mentioned, the pearl is created when an irritant element enters the oyster, which, to protect itself, surrounds it with a layer of mother-of-pearl. This pearl can be more or less round, more or less large, with more or less imperfections. Here is what determines the size and quality of the shape of this pearl:

First of all, the shape of the parasite in the oyster is very important. Indeed, if the nucleus of the parasite is not perfectly round from the start, then the pearl will not be either. This is why, for cultured pearls, farmers always make sure to introduce the roundest possible nucleus, which gives a greater majority of round pearls. of culture that of fine round pearls.

The second factor that influences the shape of a pearl is its position in the oyster. If the pearl is in the center and does not move too much, then it will grow and acquire a perfectly round shape. This is why pearls are grown near islands, where there are fewer waves, thus reducing the movement of the oyster and therefore of the pearl inside.

On the contrary, if the pearl gets too close to one of the edges of the oyster, it will take on the shape of the wall on which it is attached. These pearls are therefore assessed as being of lower quality and less prized, and described as “baroque” have a very unique charm and a so-called “vintage” appearance resulting from unique shapes created by the chance of nature.