There are five key factors that determine the quality of a pearl:


‘Lustre’ refers to the shine of a pearl. A pearl with a good lustre is often described as looking as though it is ‘glowing from within’, whereas a pearl with poor lustre will look somewhat flat and dull. When examining pearls, try and look at them in a natural light to see how well they reflect the light: the sharper the reflection, the better the lustre.


The colour of a pearl is dependent on the type of pearl and where in the world it originates. Rarer colours will be more expensive.


Just like with diamonds, the value of the pearl is not wholly determined by the size but rather their rarity, but as a general rule the larger the pearl the higher the price tends to be.


Just like other gemstones, some imperfections are to be expected. By gently rolling the pearls on a flat surface, you will be able to see any imperfections (they will show as spotting/lines or circles). These are inevitable, but the degree of imperfection or spotting will be dependent on the price. It is not unreasonable to expect medium and smaller Freshwater pearls to be very clean, but, as the size of the pearl increases you should be more tolerant of light spotting.


There are three main shapes of pearls: round, drop and baroque. Perfectly round pearls are the most desirable and therefore more expensive.