Washington state's giant clam known as the geoduck became a Chinese delicacy, creating a niche yet lucrative export. But ...

What's inside a clam? A retractable foot, a siphon for sucking up water, powerful muscles, and, sometimes, a pearl. And you thought oysters were fancy. Following is the transcript of the video.

The clam that it came from is a northern quahog called Mercenaria mercenaria, and it usually produces porcelain-like pearls ...