The Gemological Institute of America (GIA) provides a set of seven value factors for grading pearls. These are: Size, Color, Shape, Luster, Nacre Quality, Surface Quality, and Matching (within a strand or set). Traditionally, pearl farmers strived to create the perfectly round pearl. Today, Fashion gives us new, unique designs featuring pearls of interesting shapes that are far from round. This article talks about the Pearl Shape value factor, specifically, the shapes that are not created by Nature.

In the beginning, without going into too much detail, three Japanese gentlemen -- Mikimoto, Mise and Nishikawa -- developed commercial culture pearl farming as we know it today. This involved placing a round "seed" made from the shell of a mullusk shell into the Akoya oyster, thus stimulating it to make it to grow nacre (pearl skin) around that seed. Although overly simplified, this is the basic process they developed in the early 1900s that is followed still today.

Freshwater pearls are cultured a little differently. They do not require that seed bead. They begin with just a slip of mantel tissue from a donor mussel(mussels grow in freshwater; oysters in saltwater). This offers new possibilities for shaping the new pearl. First, with just a piece of mantel tissue, Chinese pearl farmers spent many years experimenting to get the gorgeous round pearls on the market today. Although no one really knows how they do it (trade secrets abound), I have heard that placing a perfectly square piece of mantel tissue as the "seed" seems to produce rounder pearls.

Freshwater pearls also come in an array of interesting shapes. Some of these are formed using seeds just like Akoyas, Tahitians and South Seas. Instead of using the round seed bead, a square tile or a round wafer is slipped into the mussel. The result is the beautiful square and coin pearls that are so popular.

Love those Petal pearls? They are actually the result of a mussel that has already grown a square or coin pearl and is allowed to form a pearl without a seed in the empty hole. When the pearl is removed from the mussel, it leaves an empty sac. If the mussel was not injured when the pearl was taken from it, the mussel can be returned to the water where it will continue excrete nacre and form another freeform pearl in the empty pearl sac. Petal pearls cost more than simpler pearls because the mussel must survive twice as long and thus require higher risk for the pearl farmer.

Almost any shape you can imagine can be created using tiles, wafers or sticks of paraffin and/or mussel shell. Crosses, tiles and coins have all been shaped using these techniques. If you are not sure if the pearls are formed by Nature or by human intervention, be sure to ask. Your retailer should be knowledgeable enough to provide this information, especially if this is a high-dollar item. Your retailer should be equally willing to disclose this information.

Beth Schmitz, CEO Avant Pearl, GIA Pearls Graduate

A jewelry designer, businesswoman and self-proclaimed diva, Ms. Schmitz spent more than 20 years in business. Her creative side took control in 2001 when she chose to dedicate her life to the jewelry industry and the smart women like her who appreciate gorgeous baubles and have the means to pay for them.

Beth's online boutique features high-end pearl jewelry from leading designers, limited-edition manufacturers and skilled craftsmen throughout the world. She holds a degree from Harvard University and an MBA from the University of Texas at Austin.