The sorting and pricing of pearls is one of the most difficult tasks that requires a background of looking at thousands of pearls, on a regular basis, and having a close knowledge of the entire production process, as well as an awareness of the international market conditions worldwide.
Unlike gemstones such as diamonds, pearls are not judged by a single international standard of quality. Various systems have been developed for grading pearls. Beauty is the most important criteria when selecting a pearl. However, there are certain grading characteristics for evaluating pearls which include: Colour, Lustre, Shape, Size, and Surface.
For all the above criteria that determine the price of a pearl, there is one more important factor that is often forgotten: the matching of pearls. There is a saying that “No two pearls are alike” and in fact nature does not even guarantee that during harvesting enough pearls of marketable quality can be harvested. It is therefore extremely difficult to find a perfect pair of pearls or a necklace that will match.
Helpful tips to judge the quality of pearl strands:
• Examine the strands on a flat white surface, e.g. white cloth, board or paper. Lustre and colour are hard to judge when pearls are suspended or on a dark surface.
• Try to examine the pearls directly under a bare light instead of away from the light. This helps bring out their lustre and true colour.
• Look for the darkest and brightest areas of the pearls on a strand. Then compare the contrast between the two. The lower the contrast and the milkier the pearl, the lower the lustre.
• Examine the reflection of light on the pearls. Generally, the less sharp and intense it is, the lower the lustre will be. Sometimes, however, a lack of sharpness is due to surface flaws rather than the overall lustre.
• Compare the lustre, colour and blemishes of individual pearls on a strand. The quality of a strand is determined by its overall appearance, not just by one pearl.
• Roll the pearls slightly to see their entire surface. The lustre, colour and blemishes not only vary from pearl to pearl, but also vary on each pearl.
• Check the regularity of size and shape (especially in graduated strands)
• If possible, lay the pearls alongside other strands and compare lustre and colour. A strand will look better when viewed next to lower quality strands rather than next to those of higher quality strands.
As a general guideline your eye is the most important judge.