Global Gemstone Certification
Pearl
Pearl
Pearls are unique because rather than being formed by minerals they are created from living organisms. Grown within the shells of mollusks, these stones are spherical in shape and calcium carbonate based. One fact which most people know about pearls is that no two pearls are the same. While they can be formed in a variety of different colors, the most common shade is either white or cream. If a piece of tissue or bead is inserted into the pearl, it will become cultured and will be coated with nacre. Regardless of whether they are cultured or not pearls will almost always be both iridescent and nacreous.
Color |
White, Blue, Green, Yellow, Orange, Brown, Pink, Purple, Gray, Black, Multicolored |
Hardness |
2.5 – 4.5 |
Crystal System |
Amorphous |
Refractive Index |
1.52 – 1.69 |
SG |
2.6 – 2.8 |
Transparency |
Opaque |
Double Refraction |
.156 |
Luster |
Pearly |
Cleavage |
None |
Mineral Class |
Calcium carbonate and conchiolin (organic) combined with water |