How to discover your own seaside keepsake.

By Yolanda Wikiel
Updated June 26, 2013
Collection of blue and green seaglass
Credit: Stephen Lewis

Want to increase your chances of happening upon some sea glass? Think like a historian. Since glass shards can take decades (or even centuries) to form into smooth, luminous artifacts, hit the beaches near old factories, Colonial-era settlements, or shipwrecks, such as Lake Erie, Pennsylvania; Gloucester, Massachusetts; or Fort Bragg, California, says S. Deacon Ritterbush, Ph.D., the author of The Beachcomber’s Odyssey. You should also have more luck after a storm or during a full moon, when strong tides can stir up buried treasures.

What to look for: Since sea glass can be tricky to spot in the sand and rocks, walk toward a rising or sinking (not overhead) sun, so the light will glint on the pieces and they’ll stand out. Sea glass comes in a spectrum of translucent and opaque shades, from frosty white, aqua, and emerald to brown, red, orange, and purple.

When to look: The peak time to search is right before or after a low tide; during full-moon periods, when tides are stronger; or after a storm, when currents may have stirred up long-buried lumps.

Where to look: Surprisingly, you don’t always have to venture to an oceanside town to find grade-A specimens. “The glass that washes up on the shores of lakes and rivers, called ‘beach glass,’ is just as beautiful as the sea variety,” says S. Deacon Ritterbush, Ph.D., an eco-educator and the creator of Whether fresh or salt, the most plentiful sites will be near old factories, centuries-old settlements, ferry runs, shipwrecks, or anywhere there was potential for glass to be deposited in the water. “Still, resources are limited, so be courteous: Take a few and leave the rest for the next person,” says Ritterbush. She recommends checking out these other glass-rich locales if you have the opportunity.

1. Bar Harbor, Maine

2. Fort Bragg, California

3. Fort Smallwood Park, Maryland

4. Gloucester, Massachusetts

5. Lake Erie, Pennsylvania

6. Lake Michigan, Michigan

7. Port Allen, Kauai, Hawaii

8. Port Townsend, Washington

9. Vieques, Puerto Rico

10. Woodland Beach, Delaware

How to spot fakes: If hitting the gift shops suits your idea of a treasure hunt, be on the lookout for imposters. Artificially made sea glass tends to have jagged edges and more intense colors. Another tip-off? “Too-perfect shards in a jar, all with uniform color, size, and shape, are probably not real,” says Ritterbush.