The stones aren't actually diamonds, but a locally sought-after, sea-polished white quartz found on the beaches of Cape May, which is hosting the festival for the first time.
"Sea glass truly is nature's gift to collectors, so it is somewhat unusual to have a festival based on something that you can't really buy in its basic form. You have to go out and find it," said Nancy LaMotte, a spokeswoman for the North American Sea Glass Association.
The group is organizing the two-day event, which is expected to bring more than 4,000 people to Cape May Convention Hall Sept. 27 and 28.
The festival is to feature lectures and discussions about sea glass as well as 50 exhibitors who will showcase and sell their wares, including jewelry, stained glass, and other art made from the material, and books and photographs on the subject.
The event will culminate with the "Shard of the Year" award. The most remarkable piece will be chosen from hundreds of entries that are expected to be submitted, and the winner will receive a $1,000 prize, LaMotte said.
Sea glass is formed from pieces of broken bottles, tableware, and even debris from shipwrecks that have tumbled around in the ocean for years. The glass gets its frosted appearance from exposure to the salt in the water.
Some colors of sea glass are common - the Kelly green and brown of old beer bottles. Others are rare, such as reds, oranges, and purples, which originate from Victorian-era lamps and taillights from early-model automobiles.
The pieces are pushed by storms and tides and deposited on beaches. Across the globe there are certain hot spots for finding sea glass, including along the Atlantic Coast from Maine to Florida. Beach glass, a less frosted version, is a category found on the banks of freshwater locales, experts say.
Some beachcombers simply collect their finds in jars, while others make them into displays or unusual jewelry.
In the days before recycling - when garbage was routinely dumped at sea - these "whispers from the past" were more common than they are now, said LaMotte, an expert on the subject, along with her husband, Richard LaMotte.
Richard LaMotte, noting that the trash-to-treasure days were ending, 10 years ago wrote Pure Sea Glass: Discovering Nature's Vanishing Gems. The book has become a kind of bible among sea glass aficionados because of its beautiful photography and detailed descriptions.
Nancy LaMotte said the sea glass association is a 3,300-member nonprofit volunteer organization founded about 10 years ago to educate collectors, consumers, and retailers, and to establish a standard by which to grade and appraise sea glass, similar to the way gemstones are graded.
Carol King Hood, a watercolor artist who often incorporates natural and architectural aspects into her work, is an avid sea glass collector.
She and her husband, Ned, often beachcomb near their Cape May Point cottage looking for pieces to add to their vast collection.
"It really puts you in touch with the sea, and it's such an interesting hobby that lets you find true treasures that you don't have to pay for," said King Hood, who has fashioned a coffee-table display for her home with the dozens of items they've found over the years.
"I'm really thrilled that the festival is going to be here this year. . . . I think it's the perfect locale," she said.
IF YOU GO
The North American Sea Glass Festival will be held 10 a.m. to 5 p.m. Sept. 27 and 28 at Cape May Convention Hall, 714 Beach Ave., Cape May.
Admission is $5. For more information:
Contact Jacqueline L. Urgo at 609-652-8382 or firstname.lastname@example.org.