Pearls-Pearl Jewelry
Black Pearls
Black Pearls are produced by the black-lipped pinctada margaritifera shell which is found in the South Pacific areas of Tahiti, Cook Islands and Kiribati.
Skilled workers start the pearl growing process by inserting a tiny starter sphere of Mississippi fresh water clam into a black-lipped pinctada margaritifera. A piece of mantle from a donor shell is also inserted.
Black pearls are black because the nacre will not reflect white light, but will reflect green, red, yellow ...etc.
Black pearls will vary from black to gray to blue to green and brown. Overtone colors on dark colored pearls are pink, blue, gold, silver and a reddish purple. Overtones may be present in a variety of combinations.
Names have been given to various color combinations:
- Peacock - greenish black
- Cherry or Aubergine - purplish black
- Champagne - yellowish gray
- Pistachio - greenish gray
- Lavender - bluish black
- Tahitian gold - golden black
- Pigeon gray - purplish gray
- Silver - gray
- Moon gray - pale gray
- Orient gray - surface iridescence
Sizes range from 8 - 12 mm commonly. Anything larger is considered rare. The record for a round Tahitian pearl is 21 mm.
Luster, shape and complexion can be graded much as any color pearl.
Tahiti cultured pearls are required to have a minimum nacre layer thickness of 0.8 mm.