Couple's once-in-a-lifetime discovery in anniversary dinner

A couple has made a potentially priceless discovery during an anniversary dinner at their favourite restaurant.

Maria and Michael Spressler from New Jersey were at The Lobster House in Cape May when Michael ordered his usual appetiser, a dozen clams in a half shell.

He was just about done when he picked up the last one and noticed it was heavier than the previous ones.

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He tells KYW-TV he started chewing he says he "actually thought one of my teeth broke".

When he spat out the offending object he and his wife were looking at a pearl.

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"He's eaten dozens and dozens of clams and we've never found anything like that so it was pretty exciting," Maria tells the news outlet.

They've been dining at the restaurant since 1987 and nothing like this has ever happened before.

It has been described as a once-in-a-lifetime discovery.

The pearl measures at 8.8 millimetres and could be worth $100,000 but the couple have no plans to sell it. Instead Maria plans to have it made into a piece of jewellery.

"It's a beautiful remembrance of that day and what we have is so special," she says.

The restaurant were delighted to hear about the couple's find, sharing it on social media.

Sarah Stadnicar, who works at the Lobster House, says she's never heard of a discovery like this.

"I have worked here for around 10 years now and I've never heard of someone finding one in one of our oysters or clamshells," she says.