A northern California couple stumbled onto what experts believe is the largest discovery of gold in the United States. The middle-aged couple, identified only as John and Mary, made the shocking find last year while out walking their dog on a piece of their property in an area known as California Gold Country.

Is the Gold Rush Moving Into Outer Space!?

They say they noticed a rusty can sticking out of the ground near an old tree. Upon further inspection, John and Mary unearthed 1,427 mint condition coins, dating from the 1800s. The coins, said to be valued at $10 million, were recently authenticated by a company in northern California.

David McCarthy, chief numismatist of Kagin's Inc., explained that the couple didn't know what to do after the discovery. So they dug a new hole, buried the gold and went about researching how to handle the next steps.

Kagin's Inc., one of the nation's top rare coin firms, is handling the sale, which will take place on Amazon.com. The question of who hid the gold there in the first place remains a mystery.

Claudia Cowan reported the details on America's Newsroom, saying the couple plans to keep living on their rural property after the windfall. They plan to keep working, donate some of the cash to charity and keep a few coins as keepsakes.

Some may think this whole story just sounds too good to be true. Like Bill Hemmer, who remains a bit skeptical.

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Read more on the story below via AP:

 A Northern California couple out walking their dog on their Gold Country property stumbled across a modern-day bonanza: $10 million in rare, mint-condition gold coins buried in the shadow of an old tree.

Nearly all of the 1,427 coins, dating from 1847 to 1894, are in uncirculated, mint condition, said David Hall, co-founder of Professional Coin Grading Service of Santa Ana, which recently authenticated them. Although the face value of the gold pieces only adds up to about $27,000, some of them are so rare that coin experts say they could fetch nearly $1 million apiece.

"I don't like to say once-in-a-lifetime for anything, but you don't get an opportunity to handle this kind of material, a treasure like this, ever," said veteran numismatist Don Kagin, who is representing the finders. "It's like they found the pot of gold at the end of the rainbow."

Kagin, whose family has been in the rare-coin business for 81 years, would say little about the couple other than that they are husband and wife, are middle-aged and have lived for several years on the rural property where the coins were found. They have no idea who put them there, he said.

The pair are choosing to remain anonymous, Kagin said, in part to avoid a renewed gold rush to their property by modern-day prospectors armed with metal detectors.

They also don't want to be treated any differently, said David McCarthy, chief numismatist for Kagin Inc. of Tiburon.

"Their concern was this would change the way everyone else would look at them, and they're pretty happy with the lifestyle they have today," he said.

They plan to put most of the coins up for sale through Amazon while holding onto a few keepsakes. They'll use the money to pay off bills and quietly donate to local charities, Kagin said.

Before they sell them, they are loaning some to the American Numismatic Association for its National Money Show, which opens Thursday in Atlanta.

What makes their find particularly valuable, McCarthy said, is that almost all of the coins are in near-perfect condition. That means that whoever put them into the ground likely socked them away as soon as they were put into circulation.

Because paper money was illegal in California until the 1870s, he added, it's extremely rare to find any coins from before that of such high quality.

"It wasn't really until the 1880s that you start seeing coins struck in California that were kept in real high grades of preservation," he said.

The coins, in $5, $10 and $20 denominations, were stored more or less in chronological order, McCarthy said, with the 1840s and 1850s pieces going into one canister until it was filed, then new coins going into the next one and the next one after that. The dates and the method indicated that whoever put them there was using the ground as their personal bank and that they weren't swooped up all at once in a robbery.

Although most of the coins were minted in San Francisco, one $5 gold piece came from as far away as Georgia.