When debris gets trapped in between the shells ... white to black — including blue, green, orange, pink, and yellow. The main factor that determines the color of pearls is the shade of the ...

akoya oyster populations should return to health, probably by the year 2002. Thinning may solve the problem, Müller says, because lower shell density usually results in a higher quality pearl.

Uma Thurman's dress had over 3,000 white ... shell of a mollusk like an oyster or a mussel. To protect itself from the invader, the mollusk starts to coat the debris with nacre, or mother-of-pearl ...