Sea of Cortez pearl
From The Gemology Project
Pearl | |
---|---|
Chemical composition | Calcium carbonate, conchiolin and water |
Crystal system | Amorphous |
Hardness | 2.5-3.5 |
Refractive index | 1.52-1.69 |
Specific gravity | 2.68-2.86 |
Lustre | Pearly |
Contents
Color
The pteria sterna mollusk is also known as the "rainbow lipped pearl oyster" and produces pearls in many colors, ranging from white to black with any overtone (such as: blue, green, violet, purple, golden, bronze and brown).
Sizes
The average size of the Sea of Cortez pearls is 8.2 to 9.8 mm, but they can get as large as 14.3 mm.
Production
- 2004: 2.8 kilograms
- 2005: 2.5 kilograms
- 2006: 2.8 kilograms
With an average weight of 1 gram, the yearly production is about 2,800 pearls.