In a dump, used glass soda bottles are a toxic eyesore. But when rolled and softened by the waves, then spit out onto a shore, they become something extraordinary: colored pieces of stone.

Dave Lee Valle is a 'glasser,' or sea glass collector. He combs beaches for real sea glass, which is decades old and has been buried by sand, uncovered by tides, and tumbled over rocks and clam ...

Helena Ekootak started combing the beach in Ulukhaktok, N.W.T. four years ago after a personal tragedy. Now she's amassed more than 2,000 pieces of sea glass and broken pottery.

It takes about 30 years for the ocean to break down glass into sea treasure, and not all beaches are capable of creating it, which is why a good sea glass beach is hard to find. The best options are ...