Pearl classification

Pearl shape is probably the most challenging element to understand for the uninitiated but it does not have to be difficult. Tahitian pearls vary wildly but can be boiled down to the following categories: Round pearls are the most classic and a good starting point. To be classed as round they must have a diameter variance of less than two percent. This means that a 10mm pearl cannot be larger than 10.2 or 9.8mm if measured across a different diameter. Semi-round pearls are usually mixed with rounds because of their strong tendency to look the same. They are allowed a diameter variance of two to five percent which becomes noticeable to the eye. Most pearls have an axis of symmetry.