Freshwater Pearl Size
Freshwater pearl size normally range from 5mm to 12mm, though some larger sizes can be found occasionally. The freshwater pearl size below 7mm is considered small in size while size ranges from 7mm to 9mm are more popular for necklaces. The freshwater pearl size above 10mm is considered rare and more valuable. The larger the freshwater pearl size, its more difficult to find out prefect round shape.
South Sea Pearl Size
South sea pearl dominate the pearl world in size and usually they are found between 9mm and 15mm in size. Sometimes it could be found in size of 20mm which is extremely rare and high in quality. South sea pearls below 10mm are considered small in size. 10mm to 12mm size is more popular for necklace while size above 13mm is considered rare and more valuable.
Japanese Akoya Pearl Size
Japanese Akoya pearl size ranges from as small as 3mm to as large as 9.5mm. Akoya pearl size below 7mm are considered small in size. 7mm to 8mm are more popular sizes for necklace while Akoya pearl size above 8mm are considered rare, more valuable and higher in quality.
Tahitian Pearl Size
Tahitian pearl size generally ranges from as small as 8mm to as large as 16mm. Tahitian pearl below 10mm is considered small in size. Pearl size ranges from 10mm to 12mm are more popular for necklace while size above 13mm is considered rare, more valuable and high in quality.
Pearl Shapes are a significant factor in determining value. The most common shapes are irregular or baroque. A pearl’s shape has no effect on quality, but certain shapes are much more rare and where gemstones are concerned, rarity relates to value.
Rarest and most desirable among pearls is the perfect round.
Shapes in order of rarity and price (other factors being equal):
- Teardrop (pendant) Button