More than a century later, the California Gold Rush shines on -- thanks to an unprecedented discovery of rare coins by a middle-aged couple in Northern California.

While the couple -- who have chosen to remain anonymous -- was walking their dog one year ago by a tree on their rural property, they stumbled upon six half-buried and rusty metal canisters containing 1,427 gold coins.

Now known as the Saddle Ridge Hoard -- for a hill near where the stash was unearthed -- the husband and wife won’t say precisely where the fortune was buried.

It is also unknown precisely how the coins ended up underground -- though the fact that they were stored chronologically suggests “that whoever put them there was using the ground as their personal bank,” reports People.

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Comprising $5, $10 and $20 denominations, a majority of the coins were minted in San Francisco between 1847 and 1894. Worth approximately $28,000 at face value, numismatists believe that, all told, the coins could fetch as much as $10 million.

They are particularly valuable, said veteran numismatist, David Kagin, who is repping the couple, because they are in such pristine condition -- and given that paper money was illegal in California until the 1870s.

"It's like they found the pot of gold at the end of the rainbow," Kagin said.

And the couple intends to cash in. Ninety percent of the bounty will be offered via Amazon’s “Collectibles” department, though prospective buyers can glimpse some of the findings tomorrow at the American Numismatic Association’s 2014 National Money Show in Atlanta.

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