So, you want to know how pearls get their color. Let's go ahead and throw out any ideas of dyed or treated pearls. I have written about dyed pearls before but I want to tell you about how natural pearls get their color. And, when you think about it, it makes perfect sense.
Let's review what a pearl is. So, there is a mollusk living a glorious life in the river or ocean. This fairly sedentary mollusk becomes a natural habitat for other organisms. In a river, maybe it is just a little moss or organic matter. In the ocean, the mollusk might be covered in barnacles or it might get a little aquatic visitor. But, usually, these mollusks are living in an ecosystem and, occasionally, these mollusks are invaded by other species. I wish I could say it is something sweet like a little piece of sand or something. More likely it is a bacteria or sea squirt or something like that. This organism or inorganic matter damages the soft inner body of the mollusk and, to heal and protect itself it creates a pearl sac and starts making a pearl. How? It uses the epithelial cells which secrete a hardening liquid. This liquid is usually secreted to make the mollusk shell. This same material is not used to coat the invader and to produce a pearl.
So, quite simply, a mollusk is using the same material it uses to make its shell to make its pearl. So, the color of the pearl will be the same color as the shell. The black lipped oyster is such a great example.
Do you see how the edge of the shell is black? And then there is some silver coloring, some brown and a silvery white color? A black lipped oyster can produce a black pearl (with all its variety of shading!), a grey colored pearl, a brown pearl or a white pearl.
When you ask how pearls get their color, know it is all in the shell!
Read more on Chocolate pearls here...
*** but also know, dye goes a long way to imitate the natural color of pearls! Any reputable pearl seller will tell you whether the pearls have been dyed or not! ***