As a first-time visitor to the South Jersey Metal Detecting Club, I have no idea what I might find.

A similar anticipation is at the heart of a hobby that lures treasure hunters, amateur archaeologists, and history buffs alike.

"You never know what's under the ground," membership officer Dan Knight, 53, a Voorhees resident, tells me. "It could be a pull tab. Or it could be a gold ring."

Says club president Rich Sammartino, 58, of Sicklerville: "Every signal is like a Christmas present. It could be a dud, or it could be great. You never know until you dig."

With its paraphernalia and methodical, if not obsessive, focus, metal detecting can seem arcane to outsiders.

And then there's that stereotype of a nerdy old guy in black socks and sandals on the beach, earnestly yearning for a beep-beep in his headphones.

The active, congenial South Jersey club is part of a national community with its own organizations, publications, podcasts - and a robust presence on social media, YouTube, and reality TV. (Check out "KG and Ringy," the dashing duo on the National Geographic channel's Diggers.)

"It's the thrill of finding something, and not knowing what the next target is going to be," says Mark Schuessler, president of the 1,500-member Federation of Metal Detector & Archaeological Clubs Inc.

"I just dug up a railroad baggage tag near an 1860 house," adds Schuessler, who lives in Upstate New York. "I'm doing the research on it now."

Knight, a heavy-construction equipment salesman, started metal detecting as a West Deptford teenager. He joined the club a few years after it was founded in 1972.

"I was mainly interested in finding money," he explains, as members arrive for the December meeting at the Haddon Heights Municipal Building.

It's a Christmas party; more than a dozen folks have brought casseroles and other goodies, and the atmosphere is like that of a family reunion. Some have brought children and grandchildren.

Knight says about 150 people are active in the organization; most are middle-aged or older, many are retired, and some no longer hunt but still enjoy socializing with folks they've known for decades.

"We have people who are interested in recovering history, or who do it for the exercise, and if they find a few dollars in loose change, that's fine," he adds.

"I'm mainly a beach hunter, and pretty much anyone who has dedicated themselves to beach hunting is looking for lost jewelry," he says.

Serendipitous bling is an accessory of choice among some members ("we like to decorate ourselves," Knight observes) as well as their significant others.

"That's 18-karat," says Bob Gregory, pointing out a lovely bracelet on the wrist of "my lady friend of 35 years," Mary Jane McCracken of Mount Laurel.

Gregory, 85, lives in Maple Shade; he sports a gold ring with a deep green stone that he found in Collingswood.

"This is a 3,000-year-old Roman coin," says Barrington resident Harold Stuart, 75. He wears the coin, which he found and authenticated during a 1980 detecting expedition in England, on a chain around his neck.

"We are competitive," notes Stuart's friend Rich Faunce, 75, of Pennsauken. "You find out about a [promising] old farm field, and you don't tell anyone else about it until you're done hunting."

Displaying "finds" of all kinds is a highlight of club gatherings; objects are displayed, boasts made, and stories told.

At the December meeting, artifacts that club members recovered mostly from debris piles along the I-95 construction zone through Center City Philadelphia in 1975, including Colonial-era clothing buckles, utensils, and ammunition, were arrayed on a table at the front of the room.

And Knight brought along a handsome coffee-table book he has created from the photographic slides that recently deceased club member Richard Tichian made of a sensational I-95 collection.

"Our members are still finding very old and valuable things," says Knight, adding that the club has a code of ethics that forbids unauthorized excavations at certain locations, such as historic sites.

"You can't just wander onto the Red Bank battlefield and find stuff," he adds. "You'll go to jail."

Nevertheless, some professional archaeologists "think that if I dig up a [vintage] nail in my garden, I should call them up," Schuessler says.

"They want to be the ones who dig up everything," says Knight.

The South Jersey club (sjmdc.org) also emphasizes its public-service activities, which include assisting police investigators and returning lost items.

It annually presents an award to a member whose diligence in identifying the owner of an item found on a hunt - class rings and wedding rings turn up frequently - is the "best ambassador" for the hobby.

Knight and Schuessler hope more young people will become interested in metal detecting.

After all, there's nothing quite like "digging up a 300- or 400-year-old coin," Faunce says.

"You hold it in your hand, and you wonder: Who else has held this?"

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