How do you make a clam get pearls?

Answer 1

Pearls grow in pearl-producing mollusks. Natural pearls occur when a mollusk's mantle tissue becomes damaged either by parasitic intrusion or damage to the shell. The mantle contains epithelial cells, which are responsible for the nacre deposition on the inside of the shell. If these cells become dislodged when the mantle is damaged, they may continue to deposit nacre within the body of the mollusk, creating a pearl.

A grain of sand neverproduces a pearl. This is a myth.

Answer 2

If a grain of sand, or some other substance, gets inside an oyster's shell, its tissues will start forming layers and layers of mother-of-pearl around the grain of sand until it cannot feel the irritation any more

Answer 3

It doesn't.

The oyster makes a peal when a grain of sand gets trapped in its shell. The sand is covered layer by layer over the time it spends in the oyster until the oyster dies.