Pearls - Making Pearls

Making a Pearl
Contrary to popular belief, pearls hardly ever result from the intrusion of a grain of sand into an oyster’s shell. Instead, a pearl forms when an organic irritant, such as a wayward piece of food, becomes trapped between a mollusk’s shell and its soft tissue, called the mantle.

Let’s see one way this might happen:

	Step 1 Bivalves like this pearl oyster are filter feeders. As they siphon water over their gills for oxygen to breath, they also strain out plankton and other organic food particles.
	Step 2a Occasionally, an errant piece of food becomes lodged in nearby tissue.
	Step 2b Here we see a little copepod crustacean that has gone astray and accidentally become wedged between the oyster’s shell and fleshy mantle.

continue to Step 3 of Making a Pearl

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