Monday, June 16, 2008

How to measure the pearl size?

1. Different types of pearls have different expected size ranges.

A guide: akoyas typically range from 4-8mm, Tahitians from 8-14mm, South Sea pearls from 9-15mm, and freshwater pearls from 5-11mm. All have different expected size ranges, and anything outside the range will be reflected in the price.

If the pearl size reach or over the rang, the price will be more higher. Akoyas over 8.5mm, Tahitians over 15mm, South Sea pearls over 17mm, and freshwater pearls over 12mm.

2. Different diameter class by diameter length

Mini pearl: diameter < 5mm
Small pearl: 5mm < diameter < 5.5mm
Middle pearl: 5.5mm < diameter < 7mm
Big pearl: 7mm < diameter < 7.5mm
Large pearl: 7.8mm < diameter < 8mm
Surper large pearl: diameter > 8mm


3. How to measure the pearl size?

Usually we use the electronic digital caliper to measure the pearl size. It could measure the diameter of loose pearl and the length of pearl jewelry accurately. Except the error by temperature changing, chemical reagent contact, and moisture. The results of measurement are very accurately.