Semi-round pearls

Semi-round pearls are slightly imperfect spheres whose diameter variation rate is greater than 2% but less than 5%.
When a pearl is allowed two years to grow inside an oyster, the chances of even, perfectly spherical nacre accumulation are a long shot. One experienced seller of fine Tahiti Cultured Pearls says true rounds rarely account for more than 10% of a Tahiti Cultured Pearls farm's crop. And 5% is more the norm.